FCC ID: AFJIC-746PRO Amateur HF \ VHF Scanning Transceiver

 

INSTRUCTION MANUAL HF/VHF ALL MODE TRANSCEIVER i746PRO This device complies with Part 15 of the FCC rules. Operation is sub-

ject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. FOREWORD PRECAUTIONS We understand making you have a choice of many dif-

ferent radios in the market place.I want to take a cou-

ple of moments of your time to thank you for making your IC-746PRO your radio of choice, and hope you agree with Icoms philosophy of technology rst.Many hours of research and development went into the de-

sign of your IC-746PRO. Rather than completely redesigning all areas to create a new radio, the engineering team at Icom decided to follow in the footsteps of the IC-746 (one of the best values in the marketplace) with the new PRO. Fo-

cused on real world improvements compiled over the last few years from letters, phone calls, E-Mails and newsgroup postings the engineering team at Icom is proud to say many of these changes were compiled from a list of suggestions from you, the amateur radio operator!

FEATURES 32-bit Floating point DSPand 24-bit AD/DAconverter DSPIFFilter creates 102 types of lter types All mode capability covering 1602m 100 Watt continuous duty cycle All mode digital modulation and demodulation RTTYdemodulator and decoder Twin Pass Band Tuning RFspeech compression with selectable pass band Microphone Equalizer SSB/CW synchronous tuning EXPLICIT DEFINITIONS INSTRUCTION MANUAL READ THIS CAREFULLY before attempting to operate the transceiver. SAVE THIS INSTRUCTION MANUAL. This manual contains important safety and operating in-

structions for the IC-746PRO. EXPLICIT DEFINITIONS WORD DEFINITION RWARNING Personal injury, re hazard or electric shock may occur. CAUTION Equipment damage may occur. NOTE If disregarded, inconvenience only. No risk or personal injury, fire or electric shock. i R WARNING RF EXPOSURE! This device emits Radio Frequency (RF) energy. Extreme caution should be observed when operating this device. If you have any questions regarding RF exposure and safety standards please refer to the Federal Communications Commission Ofce of Engineering and Technologys report on Evalu-

ating Compliance with FCC Guidelines for Human Radio frequency Electromagnetic Fields (OET Bulletin 65). R WARNING HIGH VOLTAGE! NEVER attach an antenna or internal antenna connector during transmis-

sion. This may result in an electrical shock or burn. R NEVER apply AC to the [DC13.8V] jack on the trans-

ceiver rear panel. This could cause a re or ruin the trans-

ceiver. R NEVER apply more than 16 V DC, such as a 24 V battery, to the [DC13.8V] jack on the transceiver rear panel. This could cause a re or ruin the transceiver. R NEVER let metal, wire or other objects touch any in-

ternal part or connectors on the rear panel of the trans-

ceiver. This may result in an electric shock. NEVER expose the transceiver to rain, snow or any liquids. AVOID using or placing the transceiver in areas with tem-

peratures below 10C (+14F) or above +50C (+122F). Be aware that temperatures on a vehicles dashboard can exceed 80C (+176F), resulting in permanent damage to the transceiver if left there for extended periods. AVOID placing the transceiver in excessively dusty envi-

ronments or in direct sunlight. AVOID placing the transceiver against walls or putting anything on top of the transceiver. This will obstruct heat dissipation. Place unit in a secure place to avoid inadvertent use by children. During mobile operation, DO NOT operate the transceiver without running the vehicles engine. When transceiver power is ON and your vehicles engine is OFF, the vehi-

cles battery will soon become exhausted. Make sure the transceiver power is OFF before starting the vehicle. This will avoid possible damage to the trans-

ceiver by ignition voltage spikes. During maritime mobile operation, keep the transceiver and microphone as far away as possible from the magnetic navigation compass to prevent erroneous indications. BE CAREFUL! The heatsink will become hot when oper-

ating the transceiver continuously for long periods. BE CAREFUL! If a linear amplier is connected, set the transceivers RF output power to less than the linear am-

pliers maximum input level, otherwise, the linear ampli-

er will be damaged. Use Icom microphones only (supplied or optional). Other manufacturers microphones have different pin assign-

ments, and connection to the IC-746PRO may damage the transceiver. TABLE OF CONTENTS FOREWORD ........................................ i IMPORTANT ........................................ i EXPLICIT DEFINITIONS ..................... i PRECAUTIONS ................................... i TABLE OF CONTENTS ...................... ii QUICK REFERENCE GUIDE ........ I X I Installation ....................................... I I Operation ....................................... III I Your rst contact ........................... IV I Ready to call CQ? ......................... IX 1 PANEL DESCRIPTION ........... 112 I Front panel ..................................... 1 I Rear panel ...................................... 7 I LCD display .................................... 9 I Multi function switches .................. 11 I Microphone (HM-36) .................... 12 2 INSTALLATION AND CONNECTIONS ................... 1317 I Unpacking .................................... 13 I Selecting a location ...................... 13 I Grounding ..................................... 13 I Antenna connection ...................... 13 I Required connections ................... 14 I Advanced connections ................. 15 I Power supply connections ............ 16 I Linear amplier connections ......... 17 I External antenna tuner connection .................................... 17 3 BASIC OPERATION ............. 1825 I When rst applying power

(CPU resetting) ............................. 18 I Initial settings ................................ 18 I Selecting an operating band ........ 19 I Selecting VFO/memory mode ...... 20 I VFO operation .............................. 20 I Frequency setting ......................... 21 I Operating mode selection ............ 23 I Volume setting .............................. 23 I Squelch and receive (RF) sensitivity ...................................... 24 I Basic transmit operation ............... 25 I Electronic keyer functions ............ 29 I Operating RTTY (FSK) ................. 35 I RTTY functions ............................. 36 I Operating AM ............................... 40 I Operating FM ............................... 41 I Repeater operation ....................... 44 5 FUNCTIONS FOR RECEIVE

........................................... 4754 I Simple band scope ....................... 47 I Preamp/Attenuator ....................... 48 I RIT function .................................. 48 I AGC function ................................ 49 I IF lter selection ........................... 50 I IF (DSP) lter shape ..................... 51 I Noise blanker ............................... 51 I Meter peak hold function .............. 51 I Twin PBT operation ...................... 52 I Noise reduction ............................ 53 I Notch function .............................. 53 I Dial lock function .......................... 53 I Voice squelch control function ...... 54 6 FUNCTIONS FOR TRANSMIT

........................................... 5561 I VOX function ................................ 55 I Break-in function .......................... 56 I TX function ................................ 57 I Monitor function ............................ 57 I Speech compressor ..................... 58 I Transmit lter width selection ....... 58 I Split frequency operation .............. 59 I Quick split function ....................... 60 I Measuring SWR ........................... 61 7 MEMORY OPERATION ........ 6268 I Memory channels ......................... 62 I Memory channel selection ............ 62 I Programming a memory ............... 63 I Memory clearing ........................... 63 I Selecting the call channel ............. 64 I Programming the call channel ...... 64 I Frequency transferring ................. 65 I Programming scan edges ............ 66 I Assigning memory names ............ 67 I Memo pads ................................... 68 4 RECEIVE AND TRANSMIT .. 2646 I Operating SSB ............................. 26 I Operating CW ............................... 27 8 SCANS ................................. 6974 I Scan types .................................... 69 I Preparation ................................... 69 I Voice Squelch control function ..... 70 I Scan set mode ............................. 70 I Programmed scan/Fine programmed scan .............................................. 71 I Memory scan operation ................ 72 I Select memory scan ..................... 72 I F scan operation and Fine F scan

...................................................... 73 I Tone scan/DTCS code scan operation ...................................... 74 9 ANTENNA TUNER OPERATION

............................................ 7577 I Antenna connection and selection 75 I Antenna tuner operation ............... 76 I Optional external tuner operation . 77 10 DATA COMMUNICATION ..... 78 80 I Connections ................................. 78 I Packet (AFSK) operation .............. 79 I Adjusting the TNC output level ..... 80 I Data transmission speed .............. 80 11 SET MODE ............................ 8189 I General set mode ......................... 81 I Tone control set mode .................. 89 12 OPTION INSTALLATION ..... 90 91 I Opening the transceivers case .... 90 I UT-102 VOICE SYNTHESIZER UNIT ... 90 I CR-338 HIGH STABILITY CRYSTAL UNIT

..................................................... 91 13 MAINTENANCE .................... 9294 I Trouble shooting ........................... 92 I Fuse replacement ......................... 93 I Tuning dial brake adjustment ....... 93 I Resetting the CPU ........................ 94 I Frequency calibration (approximate)

..................................................... 94 14 CONTROL COMMAND ......... 9599 I Remote jack (CI-V) information .... 95 15 SPECIFICATIONS ...................... 100 16 OPTIONS.................................... 101 SUPPLIED ACCESSORIES The transceiver comes with the following accessories. Qty. q DC power cable (OPC-025D) ............................ 1 w Hand microphone (HM-36) ................................ 1 e Spare fuses (FGB 30 A) .................................... 2 r Spare fuse (FGB 5 A) ........................................ 1 t CW keyer plug (AP-330) .................................... 1 q w e r t Icom, Icom Inc. and the dom, Germany, France, Spain, Russia and/or other countries. are registered trademarks of Icom Incorporated (Japan) in the United States, the United King-

ii QUICK REFERENCE GUIDE I Installation 1. Install a ground system for DC noise suppression and RFI suppression 2. Install your DC power supply 3. Install lightning protection. This will help protect more than your gear. 1. Grounding your Shack Although your radio will operate by connecting the DC power supply and antenna, it is necessary to have a good ground system in your shack. A ground connec-

tion is the electrical contact between the common point of an electrical or electronic system and the earth. A good earth ground is necessary to prevent electrical shock, eliminate problems from RFI and DC noise. With more electronic devices being used today, it is also important to reduce RFI and EMI. Although you may not see interference in your shack, without a grounding system, your neighbors may experience in-

terference. Even though many of these devices are part 15, where they must accept interference from their surrounding environment, it is best to eliminate as much of the possible interference from your shack. If you do not have a grounding system for your shack, depending on the location of your shack, basement or ground oor, a good ground system can be as simple as a couple of ground rods driven 6 to 8 feet into the soil. When installing your IC-746PRO to your ground-

ing system, the shortest most direct connection is rec-

ommended. 2. Installing your DC Power Supply The DC power supply is a device used to convert 110/220 V AC, also know as Household current, to a steady source of 12 V DC. The perfect match to your IC-746PRO is the PS-125. This compact switching power supply is the matching power supply for your IC-746PRO with a current rat-

ing of 25 A continuous duty. This plug and play unit;

plugs into the DC jack located on the rear of the radio. PS-125 DC power socket Transceiver DC power cable Connect to an AC outlet using the supplied AC cable. I 4. Install and connect an antenna system for the ap-

propriate bands of operation 5. Connect other peripheral equipment. This includes microphones, headsets, TNC, amplifiers and any other equipment necessary to make your shack complete. NOTE: There are many publications covering proper grounding techniques. Check with your local dealer for more information and recommendations. D Some Symptoms if inadequate grounding a. Poor DC Ground 60 Hz hum on the audio either Rx or Tx without the antenna connected. If you feel a tingling sensation when you touch a metal surface. Surfaces such as the cover of your radio or power supply. b. Poor RF Ground While transmitting and you feel a tingling sensation when you touch a metal surface. Surfaces such as the cover of your radio or power supply. While transmitting, you experience interference to other electronic devices, such as the telephone, television or stereo audio systems. If you are not using the PS-125:

Connect the supplied DC power cable (OPC-025D) to the appropriate color coded terminals, then insert the DC connector into the DC jack located on the rear of the radio. AC outlet A DC power supply*

to DC power socket Transceiver Black _ Red

+

AC cable 30 A fuses Supplied DC power cable

*13.8 V; at least 23 A NOTE: Although the power supply current require-

ment is quite low during receiving, this not the case when you transmit. With many electrical devices in the shack, it is very important to verify the electrical circuit is not overloaded. 3. Installing lightning protection Although you may not live in an area with high occur-

rence for lightning storms, it is always wise to take precautions for lightning or static discharges. Proper lightning protection not only offers protection to the ham gear, but the shack and most importantly the op-

erator. 4. Installing your antenna system Whether your IC-746PRO is your rst radio or one of many, one of your key elements in a great shack is the antenna system. There are three connections on the back of your IC-746PRO, two for HF and 6 m and one for 2 m. If you are using one antenna for HF and 6 m, for simplicity, connect the antenna coax to ANT1. ANTENNA 1, 2

[Example]: ANT1 for 1.818 MHz bands ANT2 for 2150 MHz bands QUICK REFERENCE GUIDE NOTE: There are many publications covering proper lightning protection, check with your local dealer for more information and recommendations. Antenna SWR Each antenna is tuned for a specified frequency range and SWR may be increased out-of-range. When the SWR is higher than approx. 2.0:1, the transceivers power drops to protect the nal tran-

sistor. In this case, an antenna tuner is useful to match the transceiver and antenna. Low SWR al-

lows full power for transmitting even when using the antenna tuner. The IC-746PRO has an SWR meter to monitor the antenna SWR continuously. PL-259 CONNECTOR INSTALLATION EXAMPLE q 30 mm Slide the coupling ring down. Strip the cable jacket and soft solder. Coupling ring 10 mm (soft solder) 144 MHz ANTENNA Connect a VHF (60144 MHz) antenna; impedance: 50 . Your IC-746PRO is equipped with an internal antenna tuner (ATU) for operation on 1606 m. This ATU is de-

signed to work with an unbalanced 50 feedline. The purpose of the internal antenna tuner is match the im-

pedance of your antenna system to as close to a 50 load as possible. This ATU will not operate with a long wire or ladder line (450 or balanced feed-

lines). An external ATU such as the AH-4 would be necessary for this kind of operation. w e r 10 mm Soft solder 12 mm solder solder Strip the cable as shown at left. Soft sol-

der the center con-

ductor. Slide the connector body on and solder it. Screw the coupling ring the connector body. onto 30 mm 98 in 10 mm 38 in 12 mm 116 in R WARNING: Although a mag mount antenna works great on a vehicle, DO NOT use with IC-

746PRO on this type of antenna. CAUTION: Although your IC-746PRO has protec-

tion to drop down power with a high SWR, this does not completely protect the transceiver from transmission without an antenna. Make sure you have an antenna connect whenever you transmit with your radio. NOTE: There are many publications covering proper antennas and their installation, check with your local dealer for more information and recom-

mendations. II QUICK REFERENCE GUIDE 5. Connect other peripheral equipment Everyone has his or her favorite ad-on gear; now is the time to connect this gear! We will cover the basic devices that can be connected to your IC-746PRO. I Operation 1. Voice Microphones: Connect it to the eight-pin connector on the front of the radio. If you do not see the particular item you are wanting to connect, refer to the Advance Connections section starting on page 15. MICROPHONES HM-36 SM-20 2. CW CW Key: There are several types of keys or keyers that can be used with your IC-746PRO. a. Lambic Key paddle: Use a 6.35(d) mm (14) stereo plug and connect to the [ELEC-KEY] jack lo-

cated on the front of the radio. b. Straight Key: Use a 6.35(d) mm (14) mono plug and connect key to the back of the radio. c. External Keyer: Use a 6.35(d) mm (14) mono plug and connect to the back of the radio. d. Computer Keying: Use a 6.35(d) mm (14) mono plug and connect to the back of the radio. CW KEY STRAIGHT KEY

(dot)

(com)

(dash)

(+)

(_) A straight key can be used when the internal electronic keyer is turned OFF in keyer set mode. (p.34) NOTE: You will need to select the type of keyer you are using in the Keyer Set mode. There are many advanced CW functions in this set mode, until you have a full understanding of these functions change only the items necessary. III QUICK REFERENCE GUIDE 3. Other convenient items Headphones:

A 6.35(d) mm (14) mono jack for operation without using the internal or external speakers. Perfect for op-

eration without disturbing others in the room. External Speaker:

A 3.5(d) mm (18) mono jack for operation with an ex-

ternal speaker. (Input impedance: 8 /Max. input power: 5 W) HEADPHONES EXTERNAL SPEAKER SP-21 (optional) I Your rst contact Now you should have your IC-746PRO installed in your shack, and like a kid on his birthday, you are probably excited to get on the air. We would like to take you through a few basic operation steps to make your rst On The Air an enjoyable experience. D Turning on the radio 1. Before powering up your radio, you may want to make sure the following controls are set in the fol-

lowing positions:

[AF]

[NR]

[MIC GAIN]

[RF/SQL]

[CW PITCH]

: Commonly referred to as the vol-

ume: fully CCW.

: The noise reduction control: fully CCW.

: The mic gain: fully CCW.

: The control for the RF Gain and Squelch circuits: 12 oclock.

: The control for the CW pitch:

12 oclock.

[KEY SPEED] : Internal CW Keyer Speed: fully

[NOTCH]

CCW

: Control for the manual notch:

12 oclock 2. Resetting the CPU: Although you have purchased a brand new radio, some settings may be changed from the factory defaults from the CQ process. So your radio can start from Factory Defaults resetting the CPU is necessary.

[POWER]

[F-INP] [M-CL]

IV QUICK REFERENCE GUIDE D Just listening 1. Select the desired band Your IC-746PRO easy way of changing bands using the keypad located just above the tuning knob on the right hand side of the display. You will notice each switch has two sets of numbers; one set of numbers represents the band selection. Say you want to go to 20 meters or 14 MHz; you would push the [14 5]. This will immediately change the displayed operating frequency to the 20-meter band. This system is the triple band stacking regis-

ters. For more details on this system refer to p. 19. 1.8 1 3.5 2 7 3 10 4 14 5 18 6 21 7 24 8 28 9 GENE 50 0 144 ENT 2. Tune to the desired frequency Directly below the keypad is the tuning knob. This will allow you to dial in the frequency you want to oper-

ate. You will notice the tuning speed [TS] is 10 Hz res-

olutions. Page 22 will instruct you on how to set the tuning speed [TS] for 1 Hz resolution. NOTE: Although you can directly enter the fre-

quency with the keypad, using the Band Stacking Registers and the tuning knob is the most popular method of hoping around the bands. For more in-

formation regarding the direct frequency entry method, refer to p. 22. 3. Verify proper antenna has been selected. You IC-746PRO has three antenna connectors. Two for HF and 6m and a one for 2m. The selection for 2m is automatic, where the HF and 6m is user selectable for either one of the antenna jacks. For the rst time use, the antenna selector should show on the display of your radio. Verify the antenna selected on the display is the antenna port your connected your antenna. 4. Adjust audio output Adjust this control to a comfortable audio level. V Either 1 or 2 appears.

*No indicator appear during 144 MHz operation. AF RF/SQL Decreases Increases No audio output Max. audio output D What are you hearing?

Stop and focus on what you are hearing. Do you hear a lot of noise? Is the signal intelligible? Are you set up for the right mode? How about the lters?

1. Verify mode Although your IC-746PRO will automatically select USB or LSB in the HF bands, it will not select any of the other modes. You will need to select the proper mode whether CW, RTTY, AM or FM. QUICK REFERENCE GUIDE SSB CW/RTTY AM/FM Hint!

The Triple Band Stacking Registers will memorize the last three frequencies used in the band, as well as the Mode, Filter, Tuner and AGC settings. Mak-

ing band hoping much easier. 2. Reducing interference Your IC-746PRO has many features to reduce QRM and QRN from the desired signal. a. Noise Reduction: The noise reduction system on your IC-746PRO is part of the 32-bit DSP. This is used to reduce the hiss and QRM levels. To acti-

vate, push the [NR] switch located just to the right of the [PHONES] jack. NR NOTCH Decreases Increases OFF Noise reduction ON Noise reduction OFF

[NR]

[NR]

A G C D U P C M P T B W S C P Appears b. Adjusting the Noise Reduction: The noise re-

duction is completely variable on how much of the DSP Noise Reduction is used. Located just above the [NR] switch, this is where the [NR] level con-

trol. Hint!

How much [NR] will depend on the S/N ratio, Signal to Noise. Just using the [NR] may cause the signal to become distorted. To keep this from happening, using the [NR] along with the [RF GAIN] and Filter bandwidths will allow you to zero in on the desired signal with as little QRM as possible. VI QUICK REFERENCE GUIDE c. Notch: There are two notch systems on your IC-

746PRO. Automatic:The automatic notch will track up to three heterodynes. This is great for eliminating hetero-

dynes on 80 and 160 meters, and those annoying tune up signals across the band. Once selected an icon will appear A NOTCH on the display. Hint!

The Automatic Notch will not operated in the SSB data, CW or RTTY modes. Manual:The Manual notch provides 70 dB of atten-

uation to pin point an interfering signal. The 12 o-

clock position is on the operating frequency, turning the Notch knob clockwise moves the notch up the band and counter clockwise will move the notch down the band. Once selected an icon will appear NOTCH on the display. NR NOTCH Low freuency High frequency d. Filters: Your IC-746PRO has an incredible IF DSP based lter network with over 100 settings. Dial in your filters: By pushing [FILTER] for 1 sec., you enter the lter set mode. This is where you are able set the three lter presets. Across the bottom of the display you will see the BW icon. The switch di-

rectly below, along with the tuning dial, will be used to select the changes you will make.

[A/NOTCH]

[NOTCH]

A G C D U P C M P T B W S C P Notch function indicators NOTE: Your IC-746PRO is equipped with multiple AGC circuits. This allows the DSP to lter out inter-

fering signals and QRM, while also taking this in-

terference out of the AGC. Bottom line, this will ei-

ther eliminate or greatly reduce the pumping of the AGC from the interfering signal. Filter set mode indication B W Shows the selected filter and passband width. Indication while setting B W

[FILTER]

Reverses Appears While pushing [F1 BW], rotate the tuning dial to set passband width. A G C D U P C M P T B W S C P The selected filter width is indicated for approx. 1 sec. when [FILTER] is pushed. Filter selection VII QUICK REFERENCE GUIDE PBT operation example

[TWIN PBT] control d. Filters: continued On the fly adjustment: Once the adjustments have been made in the lter set mode, you can make on the y changes by using the Twin Pass Band Tuning, Twin PBT. You will be able to see the effects of the Twin PBT on the upper left hand side of the screen. One of 1, 2 or 3 is displayed for selected filter number indications. NOTE: The Twin PBT filters shift the two IF DSP lters (See Diagrams below and right). This feature allows both an IF shift as well as a narrowing of the Pass Band. Although you can narrow the pass band by shifting the two lters, this does not nar-

row both filters, thus the filter shape is not nar-

rowed. You may hear some signal artifacts pass through this lter adjustment.

[PBTC]

A G C D U P C M P T B W S C P Passband width and shifting value are indicated while [TWIN PBT] is operated. Filter set mode indication Appears when PBT is used. B W Shows the selected filter and passband width. Indication while PBT setting B W Appears when passband is shifted.

*Pushing [PBTC] for 1 sec., the shifted value return to default setting and the dot disappears. Center Passband Passband IF shift pass band IF center frequency interference desired signal inteference desired signal IF center freq. interference VIII QUICK REFERENCE GUIDE 3. RX Tone Control:

Once you have mastered your lter settings, one last feature to enable the most intelligible audio is the ac-

tual audio tone you hear. You can adjust the equal-

ization of your received audio 5dB. q Push [MENU] several time, or until M2 is shown on the display. w Push [F4 TCN] for the Tone Control set mode. e Push the appropriate mode switch to adjust SSB, AM or FM.

[F1 ]

[F2 ] [F4 TCN]

r Push [F1 ] or [F2 ] to change to the desired

[MENU]

Tuning dial component. 1. RX Bass This item adjusts the bass level of the receive audio tone from 5 dB to +5 dB in 1 dB steps. 2. RX Treble This item adjusts the treble level of the receive audio tone from 5 dB to +5 dB in 1 dB steps. We hope these pointers have been helpful. Now you are ready for the Ready to call CQ?. I Ready to call CQ?

[NR]: Max. CCW

[NOTCH]: Max. CCW R X B a s s S S B 3 O R X T r e b l e S S B 4 O

[TRANSMIT]: OFF i746PRO TUNER ANT NR NOTCH POWER TRANSMIT PHONES NR A/NOTCH ELEC-KEY AF RF/SQL

[AF]: Max. CCW MIC

[RF/SQL]: 12 oclock

[MIC GAIN]: Max. CCW HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH

[RF PWR]: Max. CCW

[CW PITCH]: 12 oclock

[KEY SPEED]: Max. CCW 1. Setting up your transmit audio The 32-bit DSP in your IC-746PRO is capable of giving you the type of transmit audio for your SSB Operation. 2. Mic Gain The microphone gain is used for proper transmit audio level for full output power. Although the hand microphone supplied with your IC-746PRO should re-

IX quire a setting of the [MIC GAIN] you should find a 1011 oclock position. 3. DSP TX Audio Pass Band The capable of changing the pass band of your trans-

mit audio, is at your nger tip. Regardless of the con-

dition of the speech compressor, you can adjust by selecting the [F4 TBW]. You will nd this located on the M1 menu. Pushing the

[F4 TBW] for 1 sec. you can step through the TX audio band pass. There are three levels of audio passband available

(Wide, Mid, and Nar). TX Audio Passband widths Wide Mid

: 2.9 kHz

: 2.6 kHz Nar

: 2.0 kHz

; Great Full Audio

; Great for operators with deep full voices

; Great for breaking through pile ups 4. Microphone Equalizer Although these bandwidths are xed, the Microphone Tone Control will give you more audio control for your Voice operation on SSB, AM, and FM modes. Your IC-746PRO is equipped with a very powerful equal-

izer system with 121 possible combinations. This is achieved by using the separate bass and treble ad-

justments. The default for both the Base and Treble is at 0 dB. Entering Microphone Tone Control set mode:

q Push [MENU] several time, or until M2 is shown on the display. w Push [F4 TCN] for the Tone Control set mode. e Push the appropriate mode switch to adjust SSB, AM, or FM. r Push [F1 ] or [F2 ] to change to the desired component. QUICK REFERENCE GUIDE A G C D U P C M P T B W S C P F 1 F 2 F 3 F 4 F 5 Push [F4]

T X B W = W I D E A G C D U P C M P T B W S C P F 1 F 2 F 3 F 4 F 5 The selected transmit filter width is displayed for approx. 1 sec. Push [F4] for 1 sec. to select the transmit filter width.

[F1 ]

[F2 ] [F4 TCN]

[MENU]

Tuning dial Hint!

Voice patterns and audio characteristics vary with each operator, therefore the [MIC GAIN], DSP TX Audio Pass Band and Microphone Tone Control settings will be different for each operator. Actual on air experimenting is necessary to get the just right sound. 1. TX Bass This item adjusts the bass level of the transmit audio tone from 5 dB to +5 dB in 1 dB steps. T X B a s s S S B 1 O 2. TX Treble This item adjusts the treble level of the transmit audio tone from 5 dB to +5 dB in 1 dB steps. T X T r e b l e S S B 2 O Verify you have selected a clear frequency and call out your CQ!

X 1 PANEL DESCRIPTION I Front panel

!4!5!6!7

!3 !2 i746PRO TUNER ANT NR NOTCH POWER TRANSMIT PHONES NR A/NOTCH ELEC-KEY AF RF/SQL MIC q w e r t HF/VHF TRANSCEIVER 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH y u i o !0 !1 q POWER SWITCH [POWER]

Push momentarily to turn power ON. Turn the optional DC power supply ON in advance. Push for 1 sec. to turn power OFF. t MICROPHONE CONNECTOR [MIC]

Accepts the supplied or optional microphone. See p. 100 for appropriate microphones. See p. 12 for microphone connector information. w TRANSMIT SWITCH [TRANSMIT]

Selects transmitting or receiving. The [TX] indicator lights red while transmitting and the

[RX] indicator lights green when the squelch is open. e HEADPHONE JACK [PHONES]

Accepts headphones. Output power: 5 mW with an 8 load. When headphones are connected, the internal speaker or connected external speaker does not function. r ELECTRONIC KEYER JACK [ELEC-KEY] (p. 14) Accepts a paddle to activate the internal electronic keyer for CW operation. Selection between the internal electronic keyer, bug-key and straight key operation can be made in keyer set mode. (p. 34) A straight key jack is separately available on the rear panel. See [KEY] on p. 7. Keyer polarity (dot and dash) can be reversed in keyer set mode. (p. 34) 4-channel memory keyer is available for your conve-

nience. (p. 30)

(dot)

(com)

(dash) y RF GAIN CONTROL/SQUELCH CONTROL

[RF/SQL] (outer control) Adjusts the RF gain and squelch threshold level. The squelch removes noise output from the speaker

(closed condition) when no signal is received. The squelch is particularly effective for FM. It is also available for other modes. 12 to 1 oclock position is recommended for any setting of the [RF/SQL] control. The control can be set as Auto (RF gain control in SSB, CW and RTTY; squelch control in AM and FM) or squelch control (RF gain is fixed at maximum) in set mode as follows. (p. 81) MODE SSB, CW RTTY AM, FM SET MODE SETTING AUTO RF GAIN SQL SQL SQL SQL RF GAIN + SQL RF GAIN + SQL RF GAIN + SQL When setting as RF gain/squelch control Noise squelch (FM mode) Squelch is open. RF gain adjustable range Recommended level Maximum RF gain S-meter squelch 1 When functioning as RF gain control

(Squelch is xed open; SSB, CW, RTTY only) Maximum RF gain Adjustable range Minimum RF gain When functioning as squelch control

(RF gain is xed at maximum.) Noise squelch threshold

(FM mode) Squelch is open. Noise squelch (FM mode) S-meter squelch threshold S-meter squelch Shallow Deep While rotating the RF gain control, noise may be heard. This comes from the DSP unit and does not indicate an equipment malfunction. u MIC GAIN CONTROL [MIC GAIN]

Adjusts microphone input gain. The transmit audio tone in SSB, AM and FM modes can be adjusted in tone control set mode. (p. 88)

How to set the microphone gain. Set the [MIC] control so that the ALC meter sometimes swings during normal voice transmission in SSB mode. Recommended level for an Icom microphone Decreases Increases MIC GAIN i AF CONTROL [AF] (inner control) Varies the audio output level from the speaker. AF RF/SQL Decreases Increases No audio output Max. audio output o RF POWER CONTROL [RF PWR]

Continuously varies the RF output power from min-

imum (less than 5 W*) to maximum (100 W*).

* AM mode: less than 5 W to 40 W Decreases Increases RF PWR PANEL DESCRIPTION 1

!0 CW PITCH CONTROL [CW PITCH] (p. 28) Shifts the received CW audio pitch and monitored CW audio pitch without changing the operating fre-

quency. The pitch can be changed from 300 to 900 Hz in approx. 25 Hz steps. Decreases Increases CW PITCH

!1 ELECTRONIC CW KEYER SPEED CONTROL

[KEY SPEED] (p. 28) Adjusts the internal electronic CW keyers speed. 6 wpm (min.) to 60 wpm (max.) can be set. Slow Fast KEY SPEED

!2 AUTO NOTCH/MANUAL NOTCH SWITCH

[A/NOTCH] (p. 53) Toggles the notch function between manual and au-

tomatic when pushed. NOTCH appears when manual; A NOTCH appears when automatic notch is selected.

!3 NOTCH CONTROL [NOTCH] (outer control; p. 53) Adjusts the notch lter frequency to remove a inter-

ference signal. NR NOTCH Low freuency High frequency

!4 ANTENNA SELECTOR SWITCH [ANT] (p. 75) Switches the antenna connector selection between ANT1 and ANT2 when pushed.

!5 NOISE REDUCTION LEVEL CONTROL [NR]

(inner control; p. 53) Adjusts the noise reduction level when the noise re-

duction is in use. Set for maximum readability. NR NOTCH Decreases Increases OFF

!6 ANTENNA TUNER SWITCH [TUNER] (pgs. 76, 77) Turns the antenna tuner ON and OFF (bypass) when pushed momentarily. Starts to tune the antenna manually when pushed for 1 sec. When the tuner cannot tune the antenna, the tuning circuit is bypassed automatically after 20 sec.

!7 NOISE REDUCTION SWITCH [NR] (p. 53) Switches the noise reduction ON and OFF. NR appears while the noise reduction is activated. 2 1 PANEL DESCRIPTION I Front panel (continued) i746PRO TUNER ANT NR NOTCH T NR A/NOTCH Y AF RF/SQL HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX

#7

#6

#5

#4

#3

#2

#1

#0 F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH

!8

!9 @0 @1

@2 @3 @4

@6@5

@7

@8

@9

!8 MULTI-FUNCTION SWITCHES [F1][F5]

@1 PREAMP/ATTENUATOR SWITCH [P.AMP/ATT]

Push to select the function indicated in the LCD display above these switches. (p. 11) Functions vary depending on the operating condition. Push to input a character for memory keyer pro-

gramming or memory name. (pgs. 31, 66)

!9 MENU SWITCH [MENU]

Push to change the set of functions assigned to the multi-function switches. Toggles between menu 1 (M1) and menu 2 (M2).

@0 MODE SWITCHES Selects the desired mode. (p. 23) Announces the selected mode when an optional UT-102 is installed. (p. 89) SSB CW/RTTY Selects USB and LSB mode alternately. Selects SSB data mode (USB-D, LSB-D) when pushed for 1 sec. in SSB mode. Selects CW and RTTY mode alternately. Switches CW and CW-R (CW reverse) mode when pushed for 1 sec. in CW mode. Switches RTTY and RTTY-R (RTTY re-

verse) mode when pushed for 1 sec. in RTTY mode. AM/FM Selects AM and FM mode alternately. Selects AM/FM data mode (AM-D, FM-D) when pushed for 1 sec. AM/FM mode.

(p. 48) Push momentarily to toggle between preamp-1 and preamp-2. P.AMP1 activates for HF all bands. P.AMP2 activates high-gain preamp for 24 MHz band and above. Push for 1 sec. to toggle the attenuator function ON and OFF.

What is the preamp?

The preamp amplies received signals in the front end cir-

cuit to improve the S/N ratio and sensitivity. Select P.AMP1 or P.AMP2 when receiving weak signals.

What is the attenuator?

The attenuator prevents a desired signal from distorting when very strong signals are near the desired frequency, or when very strong electric elds, such as from a broadcast-

ing station, are near your location.

@2 NOISE BLANKER SWITCH [NB] (p. 51) Switches the noise blanker ON and OFF when pushed. The noise blanker reduces pulse-type noise such as that generated by automobile igni-

tion systems. This function cannot be used for FM, or non-pulse-type noise. NB appears while the noise blanker is activated. Enters the noise blanker level set mode when pushed for 1 sec. 3 PANEL DESCRIPTION 1

@3 VOX/BREAK-IN SWITCH [VOX/BK-IN]

#0 RIT SWITCH [RIT] (p. 48) In SSB, AM and FM modes, push momentarily to turn the VOX function ON and OFF (p. 54); push for 1 sec. to enter VOX set mode (p. 54). In CW mode, push momentarily to turn the semi break-in, full break-in or break-in OFF (p. 56);

push for 1 sec. to enter break-in set mode (p. 56).

What is the VOX function?

The VOX function (voice operated transmission) starts trans-

mission without pushing the transmit switch or PTT switch when you speak into the microphone; then, automatically re-

turns to receive when you stop speaking.

What is the break-in function?

The break-in function switches transmit and receive with CW keying. Full break-in (QSK) can monitor the receive signal during keying.

@4 MONITOR SWITCH [MONITOR] (p. 57) Monitors your transmitted signal. Enters to monitor set mode when pushed for 1 sec.

@5 FILTER SWITCH [FILTER] (p. 50) Selects one of 3 IF lter settings. Enters the lter set mode when pushed for 1 sec.

@6 CALL SWITCH [CALL] (p. 64) Selects the call channel when pushed momentarily.

@7 TUNING DIAL (p. 21) Changes the displayed frequency, selects set mode items, etc.

@8 LOCK/SPEECH SWITCH [LOCK/SPCH]

Push momentarily to toggle the dial lock function ON and OFF. (p. 53) Pushing for 1 sec. announces the selected read-

out frequency and S-meter indication when an optional UT-102 is installed. (p. 89)

@9 RIT/TX CONTROL [RIT/TX] (pgs. 48, 56) Shifts the receive and/or transmit frequency without changing the transmit and/or receive frequency while the RIT and/or TX functions are ON. Rotate the control clockwise to increase the frequency, or rotate the control counterclockwise to decrease the frequency. The shift frequency range is 9.99 kHz in 10 Hz steps

(or 9.999 kHz in 1 Hz steps). RIT/TX Low shift High shift Turns the RIT function ON and OFF when pushed. Use the [RIT/TX] control to vary the RIT frequency. Adds the RIT shift frequency to the operating fre-

quency when pushed for 1 sec.

What is the RIT function?

The RIT (Receiver Incremental Tuning) shifts the receive fre-

quency without shifting the transmit frequency. This is useful for ne tuning stations calling you on an off-fre-

quency or when you prefer to listen to slightly different-

sounding voice characteristics, etc.

#1 CLEAR SWITCH [CLEAR] (pgs. 48, 56) Clears the RIT/TX shift frequency when pushed for 1 sec.

#2 TX SWITCH [TX] (p. 57) Turns the TX function ON and OFF when pushed. Use the [RIT/TX] control to vary the TX frequency. Adds the TX shift frequency to the operating frequency when pushed for 1 sec.

What is the TX function?

The TX shifts the transmit frequency without shifting the re-

ceive frequency. This is useful for simple split frequency op-

eration in CW, etc.

#3 MEMORY CHANNEL SELECTOR [M-CH] (p. 62) Select a memory channel. Rotate clockwise to increase the memory channel; ro-

tate counterclockwise to decrease the memory channel.

#4 VFO/MEMORY SWITCH [VFO/MEMO]

Switches the selected readout operating mode between the VFO mode and memory mode when pushed. (pgs. 20, 61) Transfers the memory contents to VFO when pushed for 1 sec. (p. 65)

#5 MEMORY CLEAR SWITCH [M-CL] (p. 62) Clears the selected readout memory channel con-

tents when pushed for 1 sec. in memory mode. The channel becomes a blank channel. This switch does not function in VFO mode.

#6 MEMORY WRITE SWITCH [MW] (p. 63) Stores the selected readout frequency and operat-

ing mode into the displayed memory channel when pushed for 1 sec. This function is available both in VFO and memory modes.

#7 PBT CLEAR SWITCH [PBTC] (p. 52) Clears the PBT settings when pushed for 1 sec. 4 1 PANEL DESCRIPTION I Front panel (continued) i746PRO NER ANT NR NOTCH NR A/NOTCH AF RF/SQL

%2

%1

%0 $9 $8 HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX

$7

$6

$5

$4

$3

$2

$1

$0

#9

#8 F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH

#8 TRANSMIT FREQUENCY CHECK SWITCH [XFC]

$4 QUICK TUNING SWITCH [TS] (p. 21) Turns the quick tuning step ON and OFF. While the quick tuning indicator is displayed, the fre-

quency can be changed in programmed kHz steps. 0.1, 1, 5, 9, 10, 12.5, 20 and 25 kHz quick tuning steps are available. Quick tuning indicator While the quick tuning step is OFF, turns the 1 Hz step ON and OFF when pushed for 1 sec. 1 Hz indication appears in and the frequency can be changed in 1 Hz steps. While the quick tuning step is ON, enters the quick tuning step set mode when pushed for 1 sec.

$5 VFO SELECT SWITCH [A/B] (p. 20) Push to toggle between VFO A and VFO B. Push for 1 sec. to equalize the frequency and op-

erating mode of the two VFOs.

(pgs. 45, 48) Monitors the transmit frequency when pushed and held. While pushing this switch, the transmit frequency can be changed with the tuning dial, keypad or memo pad. When the split lock function is turned ON, pushing [XFC]

cancels the dial lock function. (p. 60)

#9 MEMO PAD-WRITE SWITCH [MP-W] (p. 67) Programs the selected readout frequency and op-

erating mode into a memo pad. The 5 most recent entries remain in memo pads. The transmit frequency is programmed when pushed to-

gether with [XFC]. The memo pad capacity can be expanded from 5 to 10 in set mode for your convenience. (p. 84)

$0 TRANSMIT INDICATOR [TX]

Lights red while transmitting.

$1 MEMO PAD-READ SWITCH [MP-R] (p. 67) Each push calls up a frequency and operating mode in a memo pad. The 5 (or 10) most recently programmed frequencies and operating modes can be recalled, starting from the most recent. The memo pad capacity can be expanded from 5 to 10 in set mode for your convenience. (p. 84)

$2 RECEIVE INDICATOR [RX]

Lights green while receiving a signal and when the squelch is open.

$3 LOCK INDICATOR [LOCK] (p. 53) Lights when the dial lock function is activated. 5

$6 SPLIT SWITCH [SPLIT]

Turns the split function ON and OFF when pushed.(p. 59) Turns the quick split function ON, when pushed for 1 sec. (p. 60) The offset frequency is shifted from the displayed fre-

quency. The quick split function can be turned OFF using set mode. (p. 82) Turns the split function ON and sets the transmit frequency after inputting an offset frequency with the keypad (4 MHz in 1 kHz steps; p. 59).

$7 PASSBAND TUNING CONTROLS [TWIN PBT]

Adjust the receivers passband width of the DSP lter. (p. 52) Passband width and shift frequency are displayed in the multi-function switch indicator. Push [PBTC] for 1 sec. to clear the settings when not in use. Variable range is set to half of the IF filter passband width. 25 Hz steps and 50 Hz steps are available. These controls function as an IF shift control while in AM mode and when the RTTY lter is turned ON. Only the inner control may function in this case.

What is the PBT control?

General PBT function electronically narrows the IF passband width to reject interference. This transceiver uses the DSP circuit for the PBT function. TWIN PBT PBT1 PBT2 TWIN PBT TWIN PBT TWIN PBT

+

Low cut Center High cut

$8 SPLIT INDICATOR (p. 59) Lights during split operation.

$9 FREQUENCY INPUT SWITCH [F-INP] (p. 22) Push to toggle keypad input between frequency and band. The frequency input indicator lights during fre-

quency input is selected for the keypad.

%0 FREQUENCY INPUT INDICATOR (p. 22) Lights during frequency input from the keypad is enable. PANEL DESCRIPTION 1

%1 KEYPAD Pushing a key selects the operating band.

[GENE] selects the general coverage band. Pushing the same key 2 or 3 times calls up other stacked frequencies in the band. (p. 19) Icoms triple band stacking register memorizes 3 fre-

quencies in each band. After pushing [F-INP], enters a keyed frequency. Pushing [144 ENT] is necessary at the end.

(p. 22) e.g. to enter 14.195 MHz, push [F-INP] [1] [4] [] [1]

[9] [5] [144 ENT].

%2 LCD FUNCTION DISPLAY

(See pgs. 9, 10 for details.) Shows the operating frequency, function switch menus, band scope screen, memory name screen, set mode settings, etc. 6 1 PANEL DESCRIPTION I Rear panel q w e r

!5

!4

!3

!2

!1

!0 o i u y t q DC POWER SOCKET [DC 13.8V] (pgs. 14, 16) o ALC INPUT JACK [ALC] (p. 17) Accepts 13.8 V DC through the supplied DC power cable (OPC-025D). Connects to the ALC output jack of a non-Icom lin-

ear amplier. Rear panel view w ANTENNA CONNECTOR [ANT 144MHz]

e ANTENNA CONNECTOR 2 [ANT2]

r ANTENNA CONNECTOR 1 [ANT1]

(pgs. 14, 15, 17, 74) Accept a 50 antenna with a PL-259 connector.

[ANT 144MHz] for 144 MHz band only; [ANT1]

When using an optional AH-4 HF/50 MHz AUTO-

MATIC ANTENNA TUNER, connect it to the [ANT1]

connector. The internal antenna tuner activates for

[ANT2] and deactivates for [ANT1] when connecting the AH-4.

!0 ACCESSORY SOCKET 2 [ACC(2)]

!1 ACCESSORY SOCKET 1 [ACC(1)]

Enable connection of external equipment such as a linear amplifier, an automatic antenna selector/

tuner, TNC for data communications, etc. See p. 8 for socket information.

!2 STRAIGHT KEY JACK [KEY] (p. 14) Accepts a straight key or external electronic keyer with 14 inch standard plug.

[ELEC-KEY] on the front panel can be used for a straight key or external electronic keyer. Deactivate the internal electronic keyer in keyer set mode. (p. 34)

(+)

(_) t DATA SOCKET [DATA] (pgs. 15, 77) Connects a TNC (Terminal Node Controller), etc. for data communications. See p. 8 for connector information.

!3 TUNER CONTROL SOCKET [TUNER]

(pgs. 15, 76) Accepts the control cable from an optional AH-4 HF/50 MHz AUTOMATIC ANTENNA TUNER. y EXTERNAL SPEAKER JACK [EXT SP]

(pgs. 15, 100) Accepts a 48 speaker. u CI-V REMOTE CONTROL JACK [REMOTE] (p. 94) Designed for use with a personal computer for re-

mote control of transceiver functions. Used for transceive operation with another Icom CI-V transceiver or receiver. i SEND CONTROL JACK [SEND] (p. 17) Goes to ground while transmitting to control exter-

nal equipment such as a linear amplier. Max. control level: 16 V DC/0.5 A 7 If you use an external electronic keyer, make sure the voltage retained by the keyer is less than 0.4 V when the key is ON.

!4 CALIBRATION POT [CAL] (p. 93) This is used for frequency calibration. The transceiver has been adjusted and calibrated thor-

oughly at the factory. Under normal circumstances, the frequency does not need to be re-calibrated.

!5 GROUND TERMINAL [GND] (pgs. 13, 14) Connect this terminal to a ground to prevent electri-

cal shocks, TVI, BCI and other problems. PANEL DESCRIPTION 1 D DATA SOCKET DATA PIN No. NAME DESCRIPTION 1 2 3 4 5 6 1 2 3 5 4 6 Rear panel view D ACC SOCKETS DATA IN Input terminal for data transmit. (1200 bps: AFSK/9600 bps: G3RUH, GMSK) GND Common ground for DATA IN, DATA OUT and AF OUT. PTT P PTT terminal for packet operation. Connect ground to transmit data. DATA OUT Data out terminal for 9600 bps operation only. AF OUT Data out terminal for 1200 bps operation only. P SQL Squelch out terminal. Becomes high (+8 V) when the transceiver receives a signal which opens the squelch. To avoid unnecessary TNC transmission, connect squelch to the TNC to inhibit trans-

mission when receiving signals. Keep audio output at a normal level, otherwise a P SQL signal will not be output. ACC (1) PIN No. NAME DESCRIPTION SPECIFICATIONS 2 8 4 1 6 5 7 3 Rear panel view 1 2 3 4 5 6 7 8 RTTY Controls RTTY keying High level Low level Output current

: More than 2.4 V

: Less than 0.6 V

: Less than 2 mA GND Connects to ground. Connected in parallel with ACC(2) pin 2. Input/output pin. (HF/50 MHz only) Ground level HSEND Goes to ground when transmitting. Output current When grounded, transmits.

: 0.5 V to 0.8 V

: Less than 20 mA

: Less than 200 mA Input current (Tx) Connected in parallel with ACC(2) pin 3. MOD Modulator input. Connects to a modulator. Input impedance Input level

: 10 k

: Approx. 100 mV rms AF AF detector output. Fixed, regardless of [AF] position in Output level default settings. (see notes below) Output impedance : 4.7 k SQLS Squelch output. Goes to ground when squelch opens. SQL closed SQL open

: 100300 mV rms

: Less than 0.3 V/5 mA

: More than 6.0 V/100 A 13.8 V 13.8 V output when power is ON. ALC ALC voltage input. Output current Connected in parallel with ACC(2) pin 7.

: Max. 1 A Control voltage Input impedance Connected in parallel with ACC(2) pin 5.

: 4 V to 0 V

: More than 10 k ACC (2) PIN No. NAME DESCRIPTION SPECIFICATIONS 2 4 1 6 5 7 3 Rear panel view 1 2 3 4 5 6 7 8 V Regulated 8 V output. GND HSEND BAND Band voltage output.

(Varies with amateur band) Output voltage Output current

: 8 V 0.3 V

: Less than 10 mA Same as ACC(1) pin 2. Same as ACC(1) pin 3. Output voltage

: 0 to 8.0 V ALC Same as ACC (1) pin 8. Input/output pin (144 MHz only) Ground level VSEND Goes to ground when transmitting. Output current When grounded, transmits. Input current (Tx)

: 0.5 V to +0.8 V

: Less than 20 mA

: Less than 200 mA 13.8 V Same as ACC(1) pin 7. 8 1 PANEL DESCRIPTION I LCD display

!4

!3

!2

!1 q w e r t

!0 o i u y

!0 14 TUNING DIAL SPEED INDICATOR (p. 21) Appears when the tuning dial speed is set so that one rotation is equal to 14 of the normal rotation.

!1 VOICE SQUELCH CONTROL INDICATOR (p. 54) Appears during VSC (Voice Squelch Control) func-

tion is activated.

!2 MODE INDICATORs (p. 23) Shows the selected operating mode. D appears when SSB data, AM data or FM data mode is selected.

!3 ANTENNA INDICATOR (p. 75) Indicate which antenna connector is use for HF/50 MHz.

!4 ANTENNA TUNER INDICATORS (pgs. 75, 76) TUNE appears when the antenna tuner is ON;

TUNE appears and ashes during manual tun-

ing. EXT appears when the optional AH-4 external antenna tuner is connected to [ANT1]. q FREQUENCY READOUTS Show the operating frequency. w MULTI-FUNCTION METER INDICATION Shows receiving signal strength, etc. during re-

ceive. Shows transmit output power, ALC and SWR dur-

ing transmit. e VOX INDICATOR (p. 54) Appears when the VOX function is activated. r MICROPHONE COMPRESSOR INDICATOR (p. 58) Appears when the microphone compressor is acti-

vated. t MULTI-FUNCTION SWITCH INDICATOR (p. 11) Indicates the functions assigned to the multi-func-

tion switches ([F1][F5]). y DSP FILTER INDICATOR (p. 50) Shows the selected IF lter. u MEMORY CHANNEL READOUTS (p. 62) Show the selected memory channel. i SELECT MEMORY CHANNEL INDICATOR (p. 72) Appears when the selected memory channel is set as a select memory channel. o BLANK MEMORY INDICATOR (p. 62) Appears when the selected memory channel is blank. 9 I LCD display (continue)

@9 PANEL DESCRIPTION 1

!5

!6

!7

!8

!9

@0

@8

@7

@6

@5

@4

@3

@2

@1

!5 BREAK-IN INDICATORS (p. 56)

@4 NOISE REDUCTION INDICATOR (p. 53) FBK-IN appears when the full break-in function Appears when the noise reduction is activated. is activated. BK-IN appears when the semi break-in function is activated.

@5 NOTCH INDICATORS (p. 53) NOTCH appears when the manual notch func-

tion is activated.

!6 MONITOR INDICATORS (p. 57) ANOTCH appears when the automatic notch Appears when the monitor function is activated. function is activated.

!7 PREAMP INDICATORS (p. 48) Appears when the preamp is activated.

!8 ATTENUATOR INDICATORS (p. 48) Appears when the attenuator is activated.

@6 SPLIT INDICATOR (pgs. 58, 59) Appears during split operation.

@7 MEMORY INDICATOR (p. 62) Appears during memory mode.

@8 VFO INDICATORS (p. 20) Indicates whether VFO A or VFO B is selected.

@9 RIT/TX INDICATORS (pgs. 48, 56) Appears during RIT or TX operation and indicate the frequency offset.

!9 AGC INDICATORS (p. 49) Shows the selected AGC time constant. F for AGC fast; M for AGC middle; S for AGC slow; -OFF for AGC OFF.

@0 NOISE BLANKER INDICATOR (p. 51) Appears when the noise blanker is activated.

@1 DTCS INDICATOR (p. 43) Appears during DTCS operation.

@2 TONE SQUELCH INDICATORS T appears when the repeater tone is activated.

(p. 44) TSQL appears during tone squelch operation.

(p. 42)

@3 DUPLEX INDICATOR (p. 44) DUP or DUP+ appears during repeater opera-

tion. 10 1 PANEL DESCRIPTION I Multi function switches DM1 FUNCTIONS During SSB operation AGC F 1 DUP F 2 CMP F 3 TBW F 4 SCP F 5 During SSB data operation AGC F 1 DUP F 2 1/4 F 3 SCP F 5 F 4 During CW operation AGC F 1 DUP F 2 1/4 F 3 KEY F 4 SCP F 5 During RTTYoperation AGC F 1 DUP F 2 1/4 F 3 RTY F 4 SCP F 5 During AM operation AGC F 1 DUP F 2 CMP F 3 SCP F 5 F 4 During FM operation AGC F 1 DUP F 2 CMP F 3 TON F 4 SCP F 5 AGC (p. 49) AGC F 1 Push momentarily to changes the time constant of the AGC circuit. Push for 1 sec. to enter to the AGC set mode. DUPLEX (p. 44) DUP F 2 Push momentarily to selects the duplex direction or turn the function OFF. DUP or DUP+ indicator appears during duplex operation. Push for 1 sec. to turn the one-touch re-

peater function ON/OFF. SPEECH COMPRESSOR (p. 58) CMP F 3 Push momentarily to turn the speech compressor function ON/OFF. COMP indicator appears when the speech compressor is ON. Push for 1 sec. to enter to the compres-

sor set mode. 11 14 FUNCTION (p. 21) 1/4 F 3 Push to turn the 14 function ON/OFF. ON. indicator appears when the 14 function is TRANSMISSION BANDWIDTH (p. 58) TBW F 4 Push to select the transmission bandwidth. Bandwidth is selectable from narrow, middle and wide. MEMORY KEYER MENU (p. 29) KEY F 4 Push to select the memory keyer or keyer send menu, depending on the KEYER 1st Menu setting in the set mode (p. 86). RTTY MENU (p. 36) Push to select the RTTY menu. RTY F 4 BAND SCOPE FUNCTION (p. 47) Push to select the band scope screen. SCP F 5 DM2 FUNCTIONS SCN F 1 MEM F 2 SWR F 3 TCN F 4 VSC F 5 SCAN MENU (p. 70) Push to select the scan menu. SCN F 1 MEMORY NAME MENU (p. 67) Push to select the memory name screen. MEM F 2 SWR GRAPH FUNCTION (p. 61) Push to indicates the SWR graph screen. SWR F 3 TONE CONTROL SET MODE (p. 88) Push to enter the audio tone set mode. TCN F 4 VSC FUNCTION (p. 54) VSC F 5 Push to turns the VSC (Voice Squelch Control) function ON and OFF. PANEL DESCRIPTION 1 I Microphone (HM-36) q w q UP/DOWN SWITCHES [UP]/[DN]

w PTT SWITCH Change the selected readout frequency or memory channel. Continuous pushing changes the frequency or memory channel number continuously. While pushing [XFC], the transmit readout frequency can be controlled while in spilt frequency operation. The [UP]/[DN] switch can simulate a key paddle. Preset in the keyer set mode. (p. 34) MICROPHONE CONNECTOR

(Front panel view) i Main readout AF output

(varies with [AF]/[BAL]) q Microphone input w +8 V DC output u GND

(Microphone ground) y GND (PTT ground) e Frequency up/down t PTT r Main readout squelch switch Push and hold to transmit; release to receive.

[MIC]

Pin No. FUNCTION DESCRIPTION w e r

+8 V DC output Frequency up Frequency down Squelch open Squelch closed Max. 10 mA Ground Ground through 470 Low level High level CAUTION: DO NOT short pin 2 to ground as this can damage the internal 8 V regulator. NOTE: DC voltage is applied to pin 1 for micro-

phone operation. Take care when using a non-Icom microphone. HM-36 SCHEMATIC DIAGRAM MICROPHONE MICROPHONE CABLE MICROPHONE PLUG

+

10 2k 4700p

+

0.33 4700p MIC ELEMENT DOWN UP PTT RECEIVE TRANSMIT 470 q u w i y e r t 12 2 INSTALLATION AND CONNECTIONS I Unpacking After unpacking, immediately report any damage to the delivering carrier or dealer. Keep the shipping cartons. For a description and a diagram of accessory equip-

ment included with the IC-746PRO, see Supplied ac-

cessories on p. ii of this manual. I Selecting a location Select a location for the transceiver that allows ade-

quate air circulation, free from extreme heat, cold, or vibrations, and away from TV sets, TV antenna ele-

ments, radios and other electro magnetic sources. The base of the transceiver has an adjustable stand for desktop use. Set the stand to one of two angles de-

pending on your operating conditions. I Grounding To prevent electrical shock, television interference

(TVI), broadcast interference (BCI) and other prob-

lems, ground the transceiver through the GROUND terminal on the rear panel. For best results, connect a heavy gauge wire or strap to a long earth-sunk copper rod. Make the distance be-

tween the [GND] terminal and ground as short as pos-

sible. R WARNING: NEVER connect the [GND]

terminal to a gas or electric pipe, since the connec-

tion could cause an explosion or electric shock. I Antenna connection For radio communications, the antenna is of critical im-

portance, along with output power and sensitivity. Se-

lect antenna(s), such as a well-matched 50 antenna, and feedline. 1.5:1 or better of Voltage Standing Wave Ratio (VSWR) is recommended for your desired band. Of course, the transmission line should be a coaxial cable. When using 1 antenna, use the [ANT1] connector. CAUTION: Protect your transceiver from lightning by using a lightning arrestor. PL-259 CONNECTOR INSTALLATION EXAMPLE 30 mm Coupling ring 10 mm (soft solder) 10 mm Soft solder 12 mm solder solder q w e r Slide the coupling ring down. Strip the cable jacket and soft solder. Strip the cable as shown at left. Soft sol-

der the center con-

ductor. Slide the connector body on and solder it. Screw the coupling ring the connector body. onto 30 mm 98 in 10 mm 38 in 12 mm 116 in Antenna SWR Each antenna is tuned for a specified frequency range and SWR may be increased out-of-range. When the SWR is higher than approx. 2.0:1, the transceivers power drops to protect the nal transis-

tor. In this case, an antenna tuner is useful to match the transceiver and antenna. Low SWR allows full power for transmitting even when using the antenna tuner. The IC-746PRO has an SWR meter to moni-

tor the antenna SWR continuously. 13 INSTALLATION AND CONNECTIONS 2 I Required connections Front panel CW KEY

(dot)

(com)

(dash) i746PRO TUNER ANT NR NOTCH POWER TRANSMIT PHONES NR A/NOTCH ELEC-KEY AF RF/SQL MIC HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W MP-R TS XFC PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH A straight key can be used when the internal electronic keyer is turned OFF in keyer set mode. (p.34) MICROPHONES (p. 100) HM-36 SM-20

(optional) Rear panel 144 MHz ANTENNA (pgs. 13, 74) ANTENNA 1, 2 (pgs. 13, 74)

[Example]: ANT1 for 1.818 MHz bands ANT2 for 2150 MHz bands Connect a VHF

(60144 MHz) antenna;

impedance: 50 . DC POWER SUPPLY PS-125

(Optional) GROUND (p. 13) STRAIGHT KEY Use the heaviest gauge wire or strap available and make the connection as short as possible. Grounding prevents electrical shocks, TVI and other problems.

(+)

(_) 14 2 INSTALLATION AND CONNECTIONS I Advanced connections Front panel HEADPHONES i746PRO TUNER ANT NR NOTCH POWER TRANSMIT PHONES NR A/NOTCH ELEC-KEY AF RF/SQL MIC HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH MIC The AFSK modulation signal can be input from [MIC]. (p. 77) Rear panel AH-2b AH-4 (p. 76) ANTENNA 1, 2 (p. 17) Connects a linear amplifier, antenna selector, etc. When using the AH-4, it must be connected to the [ANT1]

connector.

[SEND], [ALC] (p. 17) Used for connecting a non-Icom linear ampli-

fier.

[DATA] (p. 77) EXTERNAL SPEAKER (p. 100) SP-21 ACC SOCKETS (pgs. 8, 77)

[REMOTE] (p. 94) Used for computer control and transceive operation. 15 I Power supply connections Use an optional DC power supply with a 25 A capacity and above when operating the transceiver with AC power. Refer to the diagrams below. INSTALLATION AND CONNECTIONS 2 CAUTION: Before connecting the DC power cable, check the following important items. Make sure:

The [POWER] switch is OFF. Output voltage of the power source is 1215 V when you use a non-Icom power supply. DC power cable polarity is correct. Red Black

: positive + terminal

: negative _ terminal CONNECTING PS-125 DC POWER SUPPLY PS-125 Transceiver Connect to an AC outlet using the supplied AC cable. DC power socket DC power cable CONNECTING A DC POWER SUPPLY AC outlet A DC power supply Transceiver 13.8 V; at least 23 A Black _ Red

+

to DC power socket Supplied DC power cable AC cable 30 A fuses CONNECTING A VEHICLE BATTERY Grommet NEVER connect to a 24 V battery. NOTE: Use terminals for the cable connections. _ black

+ red Crimp 12 V battery Supplied DC power cable Solder NEVER connect to a battery without supplied DC fuses, otherwise a re hazard may occur. 16 2 INSTALLATION AND CONNECTIONS I Linear amplier connections CONNECTING THE IC-PW1 Use the [ANT1] connector when connecting a linear amplier. To an antenna ACC(1) Remote control cable (supplied with the IC-PW1) ACC cable (supplied with the IC-PW1) ANT REMOTE INPUT1 Coaxial cable

(supplied with the IC-PW1) Be sure to connect the cable to the 7-pin ACC(2) jack. EXCITER 1 1&2 GND GND E T O M E R ANT1 ACC(2) IC-PW1 AC outlet

(Non-European versions: 100120/220240 V European version

: 230 V) Ground Transceiver Turn OFF the transceivers antenna tuner while tuning the IC-PW1s tuner. CONNECTING A NON-ICOM LINEAR AMPLIFIER To an antenna RF OUTPUT RF INPUT ALC SEND 50 coaxial cable ANT1 Transceiver Non-Icom linear amplifier ALC SEND R WARNING:

Set the transceiver output power and linear amplier ALC output level referring to the linear amplier instruction manual. The ALC input level must be in the range 0 V to 4 V, and the transceiver does not accept pos-

itive voltage. Non-matched ALC and RF power settings could cause a fire or ruin the linear amplier. The specifications for the SEND relay are 16 V/DC 0.5 A. If this level is exceeded, a large external relay must be used. I External antenna tuner connection CONNECTING THE AH-4 The AH-4 must be connected to [ANT1]. Coaxial cable (from AH-4) Transceiver ANT1 17 Control cable Ground AH-4 Long wire or optional AH-2b BASIC OPERATION 3 I When rst applying power (CPU resetting) Before rst applying power, make sure all connections required for your system are complete by referring to Chapter 2. Then, reset the transceiver using the fol-

lowing procedure. NOTE: When rst applying power or when operat-

ing in cold environments, the display may icker or appear faint. This is normal and will disappear once the transceiver has warmed up. q Make sure the transceiver power is OFF. w While pushing [M-CL] and [F-INP], push [POWER]

for 1 sec. to turn power ON. The internal CPU is reset. The transceiver displays its initial VFO frequency when resetting is complete. e Correct the set mode settings after resetting, if de-

sired. Resetting CLEARS all programmed contents in memory channels and returns programmed values in set mode to default values. I Initial settings After resetting the transceiver, set controls and switches as shown in the gure below.

[POWER]

[F-INP] [M-CL]

CW CCW : Counterclockwise

: Clockwise

[NR]: Max. CCW

[NOTCH]: Max. CCW

[TRANSMIT]: OFF i746PRO TUNER ANT NR NOTCH POWER TRANSMIT PHONES NR A/NOTCH ELEC-KEY AF RF/SQL

[AF]: Max. CCW MIC

[RF/SQL]: 12 oclock

[MIC GAIN]: Max. CCW HF/VHF TRANSCEIVER TWIN PBT 1.8 1 3.5 2 7 3 10 4 14 5 18 6 F-INP 21 7 24 8 28 9 SPLIT GENE 50 0 144 ENT A/B MP-W TX XFC MP-R TS RX LOCK PBTC MW V/M M-CL M-CH RIT TX CLEAR RIT/TX F 1 F 2 F 3 F 4 F 5 MENU SSB CW/RTTY AM/FM FILTER MIC GAIN RF PWR CW PITCH KEY SPEED P.AMP/ATT NB VOX/BK-IN MONITOR CALL LOCK/

SPCH

[RF PWR]: Max. CCW

[CW PITCH]: 12 oclock

[KEY SPEED]: Max. CCW 18 3 BASIC OPERATION I Selecting an operating band The transceiver has a triple band stacking register. This means that the last 3 operating frequencies and modes used on a particular band are automatically memorized. See the table below for a list of the bands available and the default settings for each register. Band keys BAND 1.8 MHz 3.5 MHz 7 MHz 10 MHz 14 MHz 18 MHz 21 MHz 24 MHz 28 MHz 50 MHz 144 MHz General REGISTER 1 1.900000 MHz CW 3.550000 MHz LSB 7.050000 MHz LSB 10.120000 MHz CW 14.100000 MHz USB 18.100000 MHz USB 21.200000 MHz USB 24.950000 MHz USB 28.500000 MHz USB 50.100000 MHz USB 145.000000 MHz FM 15.000000 MHz USB REGISTER 2 1.910000 MHz CW 3.560000 MHz LSB 7.060000 MHz LSB 10.130000 MHz CW 14.200000 MHz USB 18.130000 MHz USB 21.300000 MHz USB 24.980000 MHz USB 29.500000 MHz USB 50.200000 MHz USB 145.100000 MHz FM 15.100000 MHz USB REGISTER 3 1.915000 MHz CW 3.580000 MHz LSB 7.020000 MHz CW 10.140000 MHz CW 14.050000 MHz CW 18.150000 MHz USB 21.050000 MHz CW 24.900000 MHz CW 28.100000 MHz CW 51.000000 MHz FM 145.200000 MHz FM 15.200000 MHz USB D Using the band stacking registers q Push [14 5], then select a frequency and an operat-

ing mode. Frequency and operating mode are memorized in the rst band stacking register. w Push [14 5] again, then select another frequency and operating mode. This frequency and operating mode are memorized in the second band stacking register. e Push [14 5] again, then select another frequency and operating mode. This frequency and operating mode are memorized in the third band stacking register. When a fourth frequency and operating mode are se-

lected on a band, the rst register. set in step q, is over-

written.

[Example]: 14 MHz band 1.8 1 3.5 2 7 3 10 4 14 5 18 6 21 7 24 8 28 9 GENE 50 0 144 ENT 19 I Selecting VFO/memory mode VFO is an abbreviation of Variable Frequency Oscilla-

tor, and traditionally refers to an oscillator. Push [V/M] to switch between VFO and memory modes. Pushing [V/M] for 1 sec. transfers the contents of the se-

lected memory channel to VFO mode (p. 65). I VFO operation The transceiver has 2 VFOs and are called VFO A and VFO B. You can use the desired VFO to call up a fre-

quency and operating mode for your operation. DSelecting the VFO A/B Push [A/B] to switch between the VFO A and VFO B. VFO A or VFO B appears. BASIC OPERATION 3

[V/M]

[A/B]

Either one is appears DVFO equalization Push [A/B] for 1 sec. to equalize the undisplayed VFO condition to the displayed VFO. 3 beeps sound when the VFO equalization is completed. CONVENIENT Use two VFOs as a quick memory When you find a new station, but you wish to continue searching, the Two VFO system can be used for quick mem-

ory storage. q Push [A/B] for 1 sec. to store the displayed frequency into the undisplayed VFO. w Continue to searching for stations. e Push [A/B] to retrieve the stored frequency. r To continue searching for station, push [A/B] again. Push for 1 sec. A/B 20 3 BASIC OPERATION I Frequency setting The transceiver has several tuning methods for conve-

nient frequency tuning. DTuning with the tuning dial q Push the desired band key on the keypad 13 times. 3 different frequencies can be selected on each band with the band key. (p. 19) w Rotate the tuning dial to set the desired frequency. If the dial lock function is activated, the lock indicator lights, and the tuning dial does not function. In this case, push [LOCK/SPCH] to deactivate the lock function. (see p. 53 for details) DQuick tuning step The operating frequency can be changed in kHz steps

(0.1, 1, 5, 9, 10, 12.5, 20 or 25 kHz selectable) for quick tuning. q Push [SSB], [CW/RTTY] or [AM/FM] to select the desired operation mode. w Push [TS] momentarily to activate the quick tuning function. M appears. e Push [TS] for 1 sec. to enter the tuning step set mode. r Rotate the tuning dial to select the desired tuning step. t Push [TS] to exit the tuning step set mode. D 14 Tuning step function (SSB data, CW and RTTY only) While operating in SSB data/CW/RTTY, the 14 function is available for critical tuning. Dial rotation is reduced to 14 of normal when the 14 function is in use. While M1 is selected with [MENU], push [F3 1/4]

to toggle the 14 function ON and OFF. Band keys Tuning dial Select mode

[TS]

S S B 1 k H z 14 indicator D I A L A u t o T S 2 7 H I G H D Auto tuning step function When rotating the tuning dial rapidly, the tuning step automatically changes several times as selected. q Push [MENU] for 1 sec. to enter the set mode. w Push [F1] or [F2 ] to select the DIAL Auto TS item. e Rotate the tuning dial to select the function ON

(HIGH or LOW) and OFF. HIGH : Approx. 5 times faster LOW : Approx. 2 times faster OFF : Auto tuning step is turned OFF. r Push [MENU] to exit the set mode. 21 BASIC OPERATION 3

[TS]

1 Hz indicator Lights when kypad input is activated. Keypad

[F-INP]

DSelecting the 1 Hz step The minimum tuning step of 1 Hz can be used for ne tuning. q Push [TS] momentarily to turn the quick tuning step OFF M disappears. w Push [TS] for 1 sec. to toggle the 1 Hz tuning step ON and OFF. DBand edge warning beep When selecting a frequency that lies outside of a bands specified frequency range, a warning beep sounds. This function can be turned OFF in set mode, if de-

sired. (p. 81) DFrequency setting with the keypad The transceiver has a keypad for direct frequency entry as described below. q Push [F-INP]. F-INP indicator lights w Input the desired frequency. Input (decimal point) between the MHz units and kHz units. e Push [144 ENT] to enter the input frequency. To cancel the input, push [A/B] instead of [144 ENT].

[EXAMPLE]

14.025 MHz Push F-INP 1.8 1 10 4 GENE 50 0 3.5 2 14 5 144 ENT 706 kHz Push F-INP 50 0 GENE 21 7 50 0 18 6 144 ENT 21.280 MHz 21.245 MHz Push F-INP GENE 3.5 2 10 4 14 5 144 ENT 22 3 BASIC OPERATION I Operating mode selection SSB (USB/LSB), SSB data (USB data/LSB data), CW, CW reverse (CW-R), RTTY, RTTY-R (RTTY reverse), AM, AM data, FM and FM data modes are available in the IC-746PRO. Select the desired operation mode as follows. To select a mode of operation, push the desired mode switch momentarily. Push the switch again to toggle between USB and LSB, CW/CW-R and RTTY/RTTY-

R, AM and FM, if necessary. Push the switch for 1 sec. to toggle between CW and CW-R, RTTY and RTTY-R, or to select data mode, if necessary. See the diagram right below for the order of selection. Microphone signals are muted when data mode is selected. Selecting SSB mode Push [SSB] to select USB or LSB. USB is selected rst during above 10 MHz; or LSB is se-

lected rst during below 10 MHz operation. After USB or LSB is selected, push [SSB] to toggles be-

tween USB and LSB. After USB or LSB is selected, push [SSB] for 1 sec. to select USB data or LSB data mode, respectively. Selecting CW/RTTY mode Push [CW/RTTY] to select CW or RTTY. After CW/CW-R or RTTY/RTTY-R is selected, push

[CW/RTTY] to toggles between CW and RTTY. After CW or RTTY is selected, push [CW/RTTY] for 1 sec. to toggles between CW and CW reverse, or, RTTY and RTTY reverse mode, respectively. Selecting AM/FM mode Push [AM/FM] to select AM or FM. After AM or FM is selected, push [AM/FM] to toggles be-

tween AM and FM mode. After AM or FM is selected, push [AM/FM] for 1 sec. to select AM data or FM data mode, respectively.

[SSB] [CW/RTTY] [AM/FM]

D USB USB LSB D LSB SSB CW-R CW RTTY RTTY-R CW/RTTY D AM AM FM D FM AM/FM Push mode switch for 1 sec. Push mode switch momentarily. I Volume setting Rotate [AF] control to output a suitable audio level.

[AF] control AF RF/SQL Decreases Increases No audio output Max. audio output 23 BASIC OPERATION 3 I Squelch and receive (RF) sensitivity Adjusts the RF gain and squelch threshold level. The squelch removes noise output from the speaker

(closed position) when no signal is received. The squelch is particularly effective for FM. It is also avail-

able for other modes. The control can be set as the RF gain control only (squelch is xed open) or squelch control (RF gain is xed at maxi-

mum) in set mode (p. 81). See below right. The 11 to 12 oclock position is recommended for any set-

ting of the [RF/SQL] control.

[RF/SQL] control SET MODE RF+SQL

(default) SQL AUTO OPERATION Can be used in all modes. Functions as noise squelch or S-meter squelch in AM and FM; S-meter squelch only in other modes. Operates as a squelch control. RF gain is xed at max. sensitivity. Operates as an RF gain control in SSB, CW and RTTY. Squelch is xed open. Operates as an squelch control in AM and FM. RF gain is xed at max. sensitivity. Adjusting RF gain (Receive sensitivity) Normally, [RF/SQL] is set to the 11 oclock position. Rotate [RF/SQL] to the 11 oclock position for maxi-

mum sensitivity. Rotating counterclockwise from the maximum position re-

duces sensitivity. The S-meter indicates receive sensitivity. Adjusting squelch (Removing non-signal noise) Rotate [RF/SQL] clockwise, when receiving no signal, until the noise just disappears.

[RX] indicator light goes out. Rotating [RF/SQL] past the threshold point invokes the S-

meter squelch this allows you to set a minimum signal level needed to open the squelch. When setting as RF gain/squelch control Noise squelch (FM mode) Squelch is open. RF gain adjustable range Recommended level Maximum RF gain S-meter squelch When functioning as RF gain control (Squelch is xed open; SSB, CW, RTTY only) Maximum RF gain Adjustable range Minimum RF gain When functioning as squelch control (RF gain is xed at maximum) Noise squelch threshold

(FM mode) Squelch is open. Noise squelch (FM mode) S-meter squelch threshold S-meter squelch Shallow Deep 24 3 BASIC OPERATION I Basic transmit operation Before transmitting, monitor your selected oper-

ating frequency to make sure transmitting wont cause interference to other stations on the same frequency. DTransmitting Before transmitting, monitor your selected operating frequency to make sure transmitting wont cause inter-

ference to other stations on the same frequency. q Push [TRANSMIT] or [PTT] (microphone) to trans-

mit. The [TX] indicator lights red. w Push [TRANSMIT] again or release [PTT] (micro-

phone) to return to receive. DMicrophone gain adjustment Before transmitting, monitor your selected operating frequency to make sure transmitting wont cause inter-

ference to other stations on the same frequency. q Push [PTT] (microphone) to transmit. Talk into the microphone at your normal voice level. w While talking into the microphone, rotate [MIC GAIN] so that the ALC meter reading doesnt go outside the ALC zone (see right). w Release [PTT] (microphone) to return to receive.

[TRANSMIT]

[TX] indicator

[MIC GAIN]

[RF PWR]

ALC zone 25 RECEIVE AND TRANSMIT 4 I Operating SSB q Push a band key to select the desired band. w Push [SSB] to select LSB or USB. Below 10 MHz LSB is automatically selected; above 10 MHz USB is automatically selected. e Rotate [AF] to set audio to a comfortable listening level. r Rotate the tuning dial to tune a desired signal. S-meter indicates received signal strength. t Push [TRANSMIT] or [PTT] (microphone) to trans-

mit. The TX indicator lights red. y Speak into the microphone at your normal voice level. Adjust [MIC GAIN] at this step, if necessary. u Push [TRANSMIT] or release [PTT] (microphone) to return to receive. DConvenient functions for receive Preamp and attenuator (p. 48) Push [P.AMP/ATT] several times to set the pre-

amp OFF, preamp 1 ON or preamp 2 ON. P.AMP1, P.AMP2 or P.AMP appears when the preamp 1, preamp 2 or preamp is set to ON, respec-

tively. (depending on operating frequency band) Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. Push [P.AMP/ATT] momentarily to turn the attenuator OFF. ATT appears when the attenuator is set to ON. Noise blanker (p. 51) Push [NB] to turn the noise blanker ON and OFF. NB appears when the noise blanker is set to ON. Push [NB] for 1 sec. to enter noise blanker set mode. Noise reduction (p. 53) Push [NR] to turn the noise reduction ON and OFF. Rotate [NR] control to adjust the noise reduction level. NR appears when the noise reduction is set to ON. DConvenient functions for transmit Speech compressor (p. 58) While M1 is selected with [MENU], push [F3 CMP] to turn the speech compressor ON and OFF. COMP appears when the speech compressor is set to ON. VOX (voice operated transmit) (p. 54) Push [VOX/BK-IN] to turn the VOX function ON and OFF. VOX appears when the VOX function is set to ON.

[TRANSMIT]

[TX] indicator Band keys

[MIC GAIN]

[SSB]

Tuning dial LSB or USB appeare Auto notch lter (p. 53) Push [A/NOTCH] to turn the auto or manual notch function ON and OFF. Rotate [NOTCH] control to set attenuate frequency for manual notch operation. Twin PBT (passband tuning) (p. 52) Rotate [TWIN PBT] controls (inner/outer). Push [PBTC] to clear the settings. AGC (auto gain control) (p. 49) While M1 is selected with [MENU], push

[F1 AGC] several times to select AGC F, AGC M, AGC S or AGC OFF. VSC (voice squelch control) (p. 00) While M2 is selected with [MENU], push

[F5 VSC] to turn the VSC function ON and OFF. The VSC indicator appears when the voice squelch function is set to ON. Transmit quality monitor (p. 57) Push [MONITOR] to turn the monitor function ON and OFF. MONI appears when the monitor function is set to ON. Audio tone control (p. 88) While M2 is selected with [MENU], push [F4 TCN], select an item with [F1 ] and [F2 ] then rotate the tuning dial to adjust the audio tone. 26

[TRANSMIT]

[TX] indicator Band keys

[CW PITCH]

[CW/RTTY]

Tuning dial

[KEY SPEED]

CW or CW-R appeare Auto notch lter (p. 53) Push [A/NOTCH] to turn the auto or manual notch function ON and OFF. Rotate [NOTCH] control to set attenuate frequency for manual notch operation. Twin PBT (passband tuning) (p. 52) Rotate [TWIN PBT] controls (inner/outer). Push [PBTC] to clear the settings. AGC (auto gain control) (p. 49) While M1 is selected with [MENU], push

[F1 AGC] several times to select AGC F, AGC M, AGC S or AGC OFF. 14 function (p. 21) While M1 is selected with [MENU], push

[F3 1/4] to turn the 14 function ON and OFF. 4 RECEIVE AND TRANSMIT I Operating CW q Push a band key to select the desired band. w Push [CW/RTTY] to select CW. After CW mode is selected, push [CW/RTTY] for 1 sec. to toggle between CW and CW-R modes. e Rotate [AF] to set audio to a comfortable listening level. r Rotate the tuning dial to simultaneously tune a de-

sired signal and its side tone. S-meter indicates received signal strength. t Push [TRANSMIT] to transmit. The TX indicator lights red. y Use the electric keyer or paddle to key your CW sig-

nals. The Po meter indicates transmitted CW signal strength. u Push [TRANSMIT] to return to receive. DConvenient functions for receive Preamp and attenuator (p. 48) Push [P.AMP/ATT] several times to set the pre-

amp OFF, preamp 1 ON or preamp 2 ON. P.AMP1, P.AMP2 or P.AMP appears when the preamp 1, preamp 2 or preamp is set to ON, respec-

tively. (depending on operating frequency band) Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. Push [P.AMP/ATT] momentarily to turn the attenuator OFF. ATT appears when the attenuator is set to ON. Noise blanker (p. 51) Push [NB] to turn the noise blanker ON and OFF. NB appears when the noise blanker is set to ON. Push [NB] for 1 sec. to enter noise blanker set mode. Noise reduction (p. 53) Push [NR] to turn the noise reduction ON and OFF. Rotate [NR] control to adjust the noise reduction level. NR appears when the noise reduction is set to ON. DConvenient functions for transmit Break-in function (p. 56) Push [VOX/BK-IN] several times to set the break-

in OFF, semi break-in or full break-in. BK-IN or F BK-IN appears when the semi break-in or full break-in is set to ON, respectively. 27 RECEIVE AND TRANSMIT 4 Push for 1 sec. CW/RTTY Interference BFO Desired signal BFO Interference Desired signal CW mode (LSB side) CW-R mode (USB side)

[CW PITCH]

[KEY SPEED]

DAbout CW reverse mode CW reverse mode receives CW signals with a reverse side CW carrier point like that of LSB and USB modes. Use this mode when interfering signals are near the desired signal and you want to change the interference tone. Use when interfering signals are near a desired signal and you want to change the interference tone. q Push [CW/RTTY] several times to select CW mode. w Push [CW/RTTY] for 1 sec. to select CW or CW-R mode. Check the interfering tone. DAbout CW pitch control The received CW audio pitch and monitored CW audio can be adjusted to suit your preference (300 to 900 Hz in 25 Hz steps) without changing the operating fre-

quency. DAbout keying speed The transceivers internal electronic keyer speed can be adjusted from 6 to 60 wpm. Rotate [KEY SPEED] clockwise to increase keying speed; counterclockwise to decrease keying speed. DCW side tone function When the transceiver is in the receive condition (and the break-in function is OFF p. 56) you can listen to the tone of your CW signal without actually transmit-

ting. This allows you to match your transmit signal ex-

actly to another stations. This also convenient for CW practice. CW side tone level can be adjusted in keyer set mode (p. 33). 28 4 RECEIVE AND TRANSMIT I Electronic keyer functions The transceiver has a number of convenient functions for the electronic keyer that can be accessed from the memory keyer menu. q Push [CW/RTTY] to select CW mode. w Push [MENU] to select M1. e Push [F4 KEY] to select the memory keyer menu. The selectable menu can be changed with the keyer send menu in the set mode. (p. 86) r Push one of the multi-function keys ([F1] to [F5]) to select an item in the memory keyer menu. See the diagram below. Push [MENU] to return to the previous indication. DIN CW MODE A G C D U P 1 / 4 K E Y S C P F 1 F 2 F 3 F 4 F 5 Push [F4]

Memory keyer menu Push [MENU]

S N D E D T 0 0 1 S E T F 1 F 2 F 3 F 4 F 5 29

[MENU]

[CW/RTTY]

Keyer send menu (p. 40) Push

[F2]

Push

[F3]

Push

[F4]

Push

[F5]

M 1 M 2 M 3 M 4 - 1 F 1 F 2 F 3 F 4 F 5 Edit menu (p. 31) C Q T E S T C Q T E S T M 1 D E L S P C F 1 F 2 F 3 F 4 F 5 Contest number set mode (p. 32) N u m b e r S t y l e 1 N o r m a l F 1 F 2 F 3 F 4 F 5 Keyer set mode (p. 33) S i d e T o n e L e v e l 5 O %

1 F 1 F 2 F 3 F 4 F 5 RECEIVE AND TRANSMIT 4 0 0 1 M 1 M 2 M 3 M 4 - 1 F 1 F 2 F 3 F 4 F 5 DMemory keyer send menu Pre-set characters can be sent using the keyer send menu. Contents of the memory keyer are set using the edit menu. Transmitting q While M1 is selected in CW mode, push [F4 KEY]

to select the memory keyer menu. w Push [F2 SND] to select the keyer send menu. e Push [TRANSMIT] to set the transceiver to trans-

mit, or set the break-in function ON (p. 56). r Push one of the function keys ([F1] to [F4]) to send the contents of the memory keyer. Pushing a function key for 1 sec. repeatedly sends the contents; push any function key to cancel the transmis-

sion. The contest number counter, above [F5], is incremented each time the contents are sent. Push [F5] to reduce the contact number count by 1 when resending contents to unanswered calls. For your information When an external keypad is connected to the pin 3 and pin 7 of the [MIC] connector, the pro-

grammed contents, M1M4, can be transmitted without selecting the keyer send menu. See p. 86 for details. r Push [MENU] 2 times to return to M1. M1 send indication M2 send indication C Q T E S T C Q 0 0 1 M 1 M 2 M 3 M 4 - 1 U R 5 N N 0 0 1 B 0 0 1 M 1 M 2 M 3 M 4 - 1 F 1 F 2 Repeat send indication M2 send indication C Q T E S T C Q 0 0 1 M 1 M 2 M 3 M 4 - 1 U R 5 N N 0 0 1 B 0 0 1 M 1 M 2 M 3 M 4 - 1 Repeat indicators Count up trigger indicator Counter M3 send indication Q R Z ?

M 1 M 2 M 3 M 4 - 1 M4 send indication C F M T U 0 0 1 M 1 M 2 M 3 M 4 - 1 F 3 F 4 30 4 RECEIVE AND TRANSMIT DEditing a memory keyer The contents of the memory keyer memories can be set using the memory keyer edit menu. The memory keyer can memorize and re-transmit 4 CW key codes for often-used CW sentences, contact numbers, etc. Total capacity of the memory keyer is 50 characters per memory channel. Programming contents q Push [MENU] to select M1, then push [F4 KEY] to select the memory keyer menu. w Push [F3 EDIT] to select edit menu. Memory keyer contents of the channel 1 (M1) is indi-

cated. Push [F5] to manually increment the contest number. e Push [F1] to select the desired memory keyer chan-

nel to be edited. r Input the desired character by rotating the tuning dial or by pushing the keypad for number input. Selectable characters (with the tuning dial);

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z / ? . , * ^

NOTE:

^ is used to transmit a following word with no space such as AR. Put ^ before a text string such as ^AR, and the string AR is sent with no space.

* is used to insert the CW contact number. The contact number automatically increments by 1. This function is only available for one memory keyer channel at a time. Memory keyer channel M2 used * by default. t Push [F2 ] or [F3 ] to move the cursor back-

wards or forwards, respectively. Edit menu C Q T E S T C Q T E S T M 1 D E L S P C F 1 F 2 F 3 F 4 F 5 Move cursor left/right Input space Select M1 to M4 Clear character M2 default indication U R 5 N N * B K M 2 D E L S P C When inputting an astarisk, the counter is incremented by 1. y Repeat steps r and t to input the desired charac-

M3 default indication ters. u Push [MENU] 2 times to return to M1. Pre-programmed contents CH M1 CQ TEST CQ TEST DE JA1 JA1 TEST Contents M2 UR 5NN* BK M3 CFM TU M4 QRZ?

C F M T U M 3 D E L S P C M4 default indication Q R Z ?

M 4 D E L S P C Example display when inputting QSL TU DE JA3YUA TEST into M3. Q S L T U D E J A 3 Y M 3 D E L S P C D E J A 3 Y U A T E S T M 3 D E L S P C 31 DContest number set mode This menu is used to set the contest (serial) number and count up trigger, etc. Setting contents q Push [MENU] to select M1, then push [F4 KEY] to select the memory keyer menu. w Push [F4 001] to enter the contest number set mode. e Push [F1] or [F2 ] to select the desired set item. r Set the desired condition using the tuning dial. Push [F3] for 1 sec. to select a default condition or value. t Push [MENU] 2 times to return to M1. 1. Number Style This item sets the numbering system used for contact

(serial) numbers normal or morse cut numbers. Normal

: Does not use morse cut number

(default) 190 ANO : Sets 1 as A, 9 as N and 0 as O. 190 ANT : Sets 1 as A, 9 as N and 0 as T. 90 90 NO : Sets 9 as N and 0 as O. NT : Sets 9 as N and 0 as T. 2. Count Up Trig This item sets the count up trigger channel. M1, M2, M3 and M4 can be set. (default: M2) 3. Present Number This item shows the current number for the count up trigger channel set above. Rotate the tuning dial to change the number, or push

[F3 CLR] for 1 sec. to reset the current number to 001. RECEIVE AND TRANSMIT 4 S i d e T o n e L e v e l 5 O %

1 F 1 F 2 F 3 F 4 F 5 Set item up/down N u m b e r S t y l e 1 N o r m a l C o u n t U p T r i g M 2 2 P r e s e n t N u m b e r C L R 0 0 1 3 32 4 RECEIVE AND TRANSMIT DKeyer set mode This set mode is used to set the CW side tone, mem-

ory keyer repeat time, dash weight, paddle specica-

tions, keyer type, etc. Setting contents q Push [MENU] to select M1, then push [F4 KEY] to select the memory keyer menu. w Push [F5 SET] to select keyer set mode. e Push [F1] or [F2 ] to select the desired set item. r Set the desired condition using the tuning dial. Push [F3] for 1 sec. to select a default condition or value. t Push [MENU] 2 times to return to M1. 1. Side Tone Level This item sets the CW side tone output level. 0 to 100% in 1% step can be selected. 2. Side Tone L-lmt This item sets the CW side tone level limit. When the

[AF] control is rotated above a specied level, the CW side tone does not increase. ON OFF CW side tone level is limited. (default) CW side tone level is not limited. 3. Repeat Time When sending CW using the repeat timer, this item sets the time between transmission. 1 to 60 sec. in 1 sec. step can be selected. 4. Dot/Dash Ratio This item sets the dot/dash ratio. 1:1:2.8 to 1:1:4.5 (in 0.12 step) can be selected. Keying weight example: Morse code K DOT (fixed*) DASH DASH Weight setting:

1:1:3 (default) Weight setting:

Adjusted Adjustable range SPACE (fixed*) 33

*SPACE and DOT length can be adjusted with [KEY SPEED] only. S i d e T o n e L e v e l 5 O %

1 F 1 F 2 F 3 F 4 F 5 Set item up/down S i d e T o n e L e v e l 5 O %

1 S i d e T o n e L - l m t 2 O N R e p e a t T i m e 3 2 s D o t / D a s h R a t i o 4 1 : 1 : 3 . O RECEIVE AND TRANSMIT 4 5. Rise Time This item set the envelop time period which the output power becomes the set transmit power. 2, 4, 6 or 8 msec. can be selected. R i s e T i m e 5 4 m s About rise time Tx Key action Rx Tx output power Set Tx power level Time 6. Paddle Polarity This item sets the paddle polarity. Normal and reverse polarity can be selected. 7. Keyer Type This item selects the keyer type for [ELEC-KEY] con-

nector on the front panel. ELEC-KEY, BUG KEY and Straight key can be selected. 8. MIC U/D Keyer This item allow you to set the microphone [UP]/[DN]

keys to be used as a paddle. ON OFF

[UP]/[DN] switches can be used for CW.

[UP]/[DN] switches cannot be used for CW. NOTE: When ON is selected, the frequency and memory channel cannot be changed using the [UP]/[DN] switches. P a d d l e P o l a r i t y 6 N O R M A L K e y e r T y p e 7 E L E C - K E Y M I C U / D K e y e r 8 O F F 34 4 RECEIVE AND TRANSMIT I Operating RTTY (FSK) Before operating RTTY, be sure to consult the manual that come with your TNC. q Push a band key to select the desired band. w Push [CW/RTTY] several times to select RTTY. After RTTY mode is selected, push [CW/RTTY] for 1 sec. to toggle RTTY and RTTY-R modes. e Rotate [AF] to set audio to a comfortable listening level. r Rotate the tuning dial to tune a desired signal. S-meter indicates received signal strength. If the received signal cannot be demodulated, try select-

ing RTTY-R mode. t Push [TRANSMIT] to set the transceiver to the transmit condition or transmit a SEND signal from your TNC. The TX indicator lights red. The Po meter indicates transmitted RTTY signal strength. y Operate the connected PC or TNC (TU) to transmit RTTY (FSK) signals. Adjust [MIC GAIN] at this step, if necessary. u Push [TRANSMIT] to return to receive. DConvenient functions for receive Preamp and attenuator (p. 48) Push [P.AMP/ATT] several times to set the pre-

amp OFF, preamp 1 ON or preamp 2 ON. P.AMP1, P.AMP2 or P.AMP appears when the preamp 1, preamp 2 or preamp is set to ON, respec-

tively. (depending on operating frequency band) Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. Push [P.AMP/ATT] momentarily to turn the attenuator OFF. ATT appears when the attenuator is set to ON. Noise blanker (p. 51) Push [NB] to turn the noise blanker ON and OFF. NB appears when the noise blanker is set to ON. Push [NB] for 1 sec. to enter noise blanker set mode. DConvenient functions for transmit Transmit quality monitor (p. 57) Push [MONITOR] to turn the monitor function ON and OFF. MONI appears when the monitor function is set to ON. 35

[TRANSMIT]

[TX] indicator Band keys

[CW/RTTY]

Tuning dial RTTY or RTTY-R appeared Noise reduction (p. 53) Push [NR] to turn the noise reduction ON and OFF. Rotate [NR] control to adjust the noise reduction level. NR appears when the noise reduction is set to ON. Twin PBT (passband tuning) (p. 52) Rotate [TWIN PBT] controls (inner/outer). Push [PBT C] to clear the settings. AGC (auto gain control) (p. 49) While M1 is selected with [MENU], push

[F1 AGC] several times to select AGC F, AGC M, AGC S or AGC OFF. 14 function (p. 21) While M1 is selected with [MENU], push

[F3 1/4] to turn the 14 function ON and OFF. RECEIVE AND TRANSMIT 4 I RTTY functions The transceiver has a number of convenient functions for the RTTY operation that can be accessed from the RTTY menu. q Push [CW/RTTY] to select RTTY mode. w Push [MENU] to select M1. e Push [F4 RTY] to select the RTTY menu. r Push one of the multi-function keys ([F2], [F4] or

[F5]) to select an item in the RTTY menu. See the diagram below. Push [MENU] to return to the previous indication. DIN RTTY MODE

[MENU]

[CW/RTTY]

A G C D U P 1 / 4 R T Y S C P D E C F I L S E T Switches RTTY filter ON and OFF. F 1 F 2 F 3 F 4 F 5 Push [F4]

RTTY menu R T T Y - F I L O N D E C F I L S E T F 1 F 2 F 3 F 4 F 5 Push

[F4]

RTTY filter set mode (p. 37) Push

[F4] for 1 sec. B a n d W i d t h 1 3 5 O F 1 F 2 F 3 F 4 F 5 F 1 F 2 F 3 F 4 F 5 Push [F2]

RTTY decoder screen (p. 38) A D J Push

[F5]

RTTY set mode (p. 39) R T T Y M a r k 1 2 1 2 5 F 1 F 2 F 3 F 4 F 5 F 1 F 2 F 3 F 4 F 5 DAbout RTTY reverse mode Received characters are occasionally garbled when the receive signal is reversed between MARK and Space. This reversal can be caused by incorrect TNC connections, setting, commands, etc. To receive re-

versed RTTY signal correctly, select RTTY-R mode. While RTTY mode is selected, push [CW/RTTY]

for 1 sec. to select the RTTY reverse mode. RTTY-R appears when the RTTY reverse mode is se-

lected. Push [CW/RTTY] for 1 sec. again to select the normal RTTY mode. Normal Reverse 170 Hz 2125 Hz 2125 Hz 170 Hz Space Mark BFO BFO Space Mark 36 4 RECEIVE AND TRANSMIT DRTTY lter/Twin peak lter The transceiver has 5 RTTY lters in addition to nor-

mal IF filters. The passband width can be selected from 1 kHz, 500 Hz, 350 Hz, 300 Hz and 250 Hz. When the RTTY lter is turned ON, the RTTY tuning meter can be used. Moreover, the twin peak lter changes the receive fre-

quency response by boosting 2 particular frequencies

(2125 and 2295 Hz) for better copying of desired RTTY signals. RTTY lter and twin peak lter setting q Push [CW/RTTY] to select RTTY mode. After RTTY mode is selected, push [CW/RTTY] for 1 sec. to select RTTY-R mode. w Push [MENU] several times to select M1. e Push [F4 RTY] to select RTTY menu. r Push [F4 FIL] to turn the RTTY lter ON and OFF. When the RTTY lter is turned ON, the normal IF lter number indication (1, 2 or 3) disappear. t Push [F4 FIL] for 1 sec. to enter RTTY filter set mode (see below). y Push [F1] to select bandwidth item. u Rotate the tuning dial to select the RTTY lter width from 1 kHz, 500 Hz, 350 Hz, 300 Hz and 250 Hz. Push [F3] for 1 sec. to select a default value. i Push [F2 ] to select twin peak lter item. The received audio volume may become greater when the twin peak lter is turned ON. o Rotate the tuning dial to turn the twin peak filter function ON and OFF.

!0 Push [MENU] 2 times to return to M1. RTTY lter set mode 1. Band Width This item sets the RTTY lter width. 250, 300, 350, 500 Hz and 1 kHz can be selected. 2. Twin Peak FIL This item turn the twin peak lter ON and OFF. 37 A G C D U P 1 / 4 R T Y S C P F 1 F 2 F 3 F 4 F 5 RTTY filter indicator Rotate the tuning dial at the point where the both sides of dots are appeared equality. Push [F4]

R T T Y - F I L O N D E C F I L S E T F 1 F 2 F 3 F 4 F 5 Disappears when the RTTY filter is turned OFF. B a n d W i d t h 1 3 5 O T w i n P e a k F I L O N 2 DRTTY decoder The transceiver has an RTTY decoder for Baudot

(mark freq.: 2125 Hz, shift freq.: 170 Hz, 45 bps). An external terminal unit (TU) or terminal node con-

nector (TNC) is not necessary for receiving a Baudot signal. q Push [CW/RTTY] to select RTTY mode. After RTTY mode is selected, push [CW/RTTY] for 1 sec. to select RTTY-R mode. w Push [MENU] several times to select M1. e Push [F4 RTY] to select RTTY menu. r Push [F4 FIL] to turn the RTTY lter ON. The RTTY decoder does not function when the RTTY l-

ter is turned OFF. t Push [F2 DEC] to turn the RTTY decoder ON. RTTY decoder screen appears. y Push [F2] to freeze the current screen. H appears while the function is in use. u Push [F3] for 1 sec. to clear the displayed charac-

ters. i Push [MENU] to exit the RTTY decoder screen. Setting the decoder threshold level Adjust the RTTY decoder threshold level if some char-

acters are displayed when no signal is received. q Call up the RTTY decoder screen as described at above. w Push [F1 ADJ] to select the threshold level setting condition. e Rotate the tuning dial to adjust the RTTY decoder threshold level. Push [F3] for 1 sec. to select the default condition. r Push [MENU] to exit the RTTY decoder screen. RECEIVE AND TRANSMIT 4 A G C D U P 1 / 4 R T Y S C P F 1 F 2 F 3 F 4 F 5 Push [F4]

R T T Y - F I L O N D E C F I L S E T F 1 F 2 F 3 F 4 F 5 Push [F2]

A D J F 1 F 2 F 3 F 4 F 5 Appears while the RTTY decoder screen is freezed with [F2] operation. Push [F3] to erase the displayed characters. A D J F 1 F 2 F 3 F 4 F 5 Push [F1]

9 A number of indicating line, the UnShift On Space

(USOS) function and new line code can be set in the RTTY set mode. (p. 39) F 1 F 2 F 3 F 4 F 5 Threshold level indication 38 4 RECEIVE AND TRANSMIT DRTTY set mode This set mode is used to set the mark and shift fre-

quencies, keying type, decode USOS function, etc. Setting contents q Push [MENU] to select M1, then push [F4 RTY] to select the RTTY menu. w Push [F5 SET] to select RTTY set mode. e Push [F1] or [F2 ] to select the desired set item. r Set the desired condition using the tuning dial. Push [F3] for 1 sec. to select a default condition or value. t Push [MENU] 2 times to return to M1. 1. RTTY Mark Sets the mark frequency for RTTY operation. 1275, 1615 and 2125 Hz are selectable. 2. RTTY Shift Sets the shift frequency for RTTY operation. 170, 200 and 425 Hz are selectable. 3. RTTY Keying Selects the keying polarity from normal and reverse. NORMAL Key open/close = Mark/Space REVERSE Key open/close = Space/Mark 4. Decode USOS Turn the USOS (UnShift On Space) function ON/OFF ON OFF Decode as letter code Decode as character code 5. Decode New Line Selects the new line code of the internal RTTY decoder. CR: Carriage Return; LF: Line Feed CR,LF,CR+LF CR+LF CR, LF and CR+LF CR+LF only 6. Decode Screen Selects a number of the decoder indication from 2 line and 3 line. 39 R T T Y M a r k 1 2 1 2 5 F 1 F 2 F 3 F 4 F 5 Set item up/down R T T Y M a r k 1 2 1 2 5 R T T Y S h i f t 2 1 7 O R T T Y K e y i n g 3 N O R M A L D e c o d e U S O S 4 O N D e c o d e N e w L i n e C R , L F , C R + L F 5 D e c o d e S c r e e n 6 3 l i n e RECEIVE AND TRANSMIT 4

[TRANSMIT]

[TX] indicator Band keys

[MIC GAIN]

[AM/FM] Tuning dial Appears I Operating AM q Push a band key to select the desired band. w Push [AM/FM] to select AM. e Rotate [AF] to set audio to a comfortable listening level. r Rotate the tuning dial to tune a desired signal. S-meter indicates received signal strength. The default tuning step for AM mode is 1 kHz; this can be changed using tuning step program mode. (p. 21) t Push [TRANSMIT] or [PTT] (microphone) to trans-

mit. The TX indicator lights red. y Speak into the microphone at your normal voice level. Adjust [MIC GAIN] at this step, if necessary. u Push [TRANSMIT] or release [PTT] (microphone) to return to receive. DConvenient functions for receive Preamp and attenuator (p. 48) Push [P.AMP/ATT] several times to set the pre-

amp OFF, preamp 1 ON or preamp 2 ON. P.AMP1, P.AMP2 or P.AMP appears when the preamp 1, preamp 2 or preamp is set to ON, respec-

tively. (depending on operating frequency band) Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. Push [[p.AMP/ATT] momentarily to turn the attenuator OFF. ATT appears when the attenuator is set to ON. Noise blanker (p. 51) Push [NB] to turn the noise blanker ON and OFF. NB appears when the noise blanker is set to ON. Push [NB] for 1 sec. to enter noise blanker set mode. Noise reduction (p. 53) Push [NR] to turn the noise reduction ON and OFF. Rotate [NR] control to adjust the noise reduction level. NR appears when the noise reduction is set to ON. DConvenient functions for transmit Speech compressor (p. 58) While M1 is selected with [MENU], push [F3 CMP] to turn the speech compressor ON and OFF. COMP appears when the speech compressor is set to ON. VOX (voice operated transmit) (p. 54) Push [VOX/BK-IN] to turn the VOX function ON and OFF. VOX appears when the VOX function is set to ON. Auto notch lter (p. 53) Push [A/NOTCH] to turn the auto or manual notch lter ON and OFF. Rotate [NOTCH] control to set attenuate frequency for manual notch operation. IF shift (p. 52) Rotate [TWIN PBT] controls (inner only). Push [PBTC] to clear the settings. AGC (auto gain control) (p. 49) While M1 is selected with [MENU], push [F1 AGC] several times to select AGC F, AGC M, AGC S or AGC OFF. VSC (voice squelch control) (p. 00) While M2 is selected with [MENU], push

[F5 VSC] to turn the VSC function ON and OFF. The VSC indicator appears when the voice squelch function is set to ON. Transmit quality monitor (p. 57) Push [MONITOR] to turn the monitor function ON and OFF. MONI appears when the monitor function is set to ON. Audio tone control (p. 88) While M2 is selected with [MENU], push [F4 TCN], select an item with [F1 ] and [F2 ] then rotate the tuning dial to adjust the audio tone. 40 4 RECEIVE AND TRANSMIT I Operating FM q Push a band key to select the desired band. w Push [AM/FM] to select FM. e Rotate [AF] to set audio to a comfortable listening level. r Rotate the tuning dial to tune a desired signal. S-meter indicates received signal strength. t Push [TRANSMIT] or [PTT] (microphone) to trans-

mit. The TX indicator lights red. y Speak into the microphone at your normal voice level. Adjust [MIC GAIN] at this step, if necessary. u Push [TRANSMIT] or release [PTT] (microphone) to return to receive.

[TRANSMIT]

[TX] indicator Band keys

[MIC GAIN]

[AM/FM] Tuning dial Appear DConvenient functions for receive Preamp and attenuator (p. 48) Push [P.AMP/ATT] several times to set the pre-

amp OFF, preamp 1 ON or preamp 2 ON. P.AMP1, P.AMP2 or P.AMP appears when the preamp 1, preamp 2 or preamp is set to ON, respec-

tively. (depending on operating frequency band) Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. Push [[p.AMP/ATT] momentarily to turn the attenuator OFF. ATT appears when the attenuator is set to ON. Noise blanker (p. 51) Push [NB] to turn the noise blanker ON and OFF. NB appears when the noise blanker is set to ON. Push [NB] for 1 sec. to enter noise blanker set mode. DConvenient functions for transmit Speech compressor (p. 58) While M1 is selected with [MENU], push [F3 CMP] to turn the speech compressor ON and OFF. COMP appears when the speech compressor is set to ON. VOX (voice operated transmit) (p. 54) Push [VOX/BK-IN] to turn the VOX function ON and OFF. VOX appears when the VOX function is set to ON. Noise reduction (p. 53) Push [NR] to turn the noise reduction ON and OFF. Rotate [NR] control to adjust the noise reduction level. NR appears when the noise reduction is set to ON. Auto notch lter (p. 53) Push [A/NOTCH] to turn the auto or manual notch lter ON and OFF. Rotate [NOTCH] control to set attenuate frequency for manual notch operation. VSC (voice squelch control) (p. 00) While M2 is selected with [MENU], push

[F5 VSC] to turn the VSC function ON and OFF. The VSC indicator appears when the voice squelch function is set to ON. Transmit quality monitor (p. 57) Push [MONITOR] to turn the monitor function ON and OFF. MONI appears when the monitor function is set to ON. Audio tone control (p. 88) While M2 is selected with [MENU], push [F4 TCN], select an item with [F1 ] and [F2 ] then rotate the tuning dial to adjust the audio tone. 41 DTone squelch operation Tone squelch operation is a method of communica-

tions using selective calling. Only received signal hav-

ing a matching tone will open the squelch. Before communicating using tone squelch, all members of your party must agree on the tone squelch frequency to use. q Push [AM/FM] to select FM mode. w Push [MENU] several times to select M1. e Push [F4 TON] several times to turn the tone squelch function ON. TSQL appears r Push [F4 TONE] for 1 sec. to enter tone frequency set mode. t Push [F1 TON] several times until TSQL Tone appears, if necessary. y Rotate the tuning dial to select the desired tone squelch frequency. Push [F3] for 1 sec. to select the default frequency. u Push [MENU] to return to M1. i Communicate in the usual manner. RECEIVE AND TRANSMIT 4 A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Push [F4] for 1 sec. T S Q L T o n e T O N S C N 8 8 . 5 H z F 1 F 2 F 3 F 4 F 5 Available tone squelch frequencies 186.2 189.9 192.8 196.6 199.5 203.5 206.5 165.5 167.9 171.3 173.8 177.3 179.9 183.5 085.4 088.5 091.5 094.8 097.4 100.0 103.5 107.2 110.9 114.8 118.8 123.0 127.3 131.8 136.5 141.3 146.2 151.4 156.7 159.8 162.2 67.0 69.3 71.9 74.4 77.0 79.7 82.5

(Unit: Hz) 254.1 210.7 218.1 225.7 229.1 233.6 241.8 250.3 42 A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Push [F4] for 1 sec. D T C S C o d e T O N S C N O 2 3 - N N F 1 F 2 F 3 F 4 F 5 Select a code with the tuning dial. Push [F5] to select the polarity 4 RECEIVE AND TRANSMIT DDTCS operation DTCS function is an another method of communica-

tions using selective calling. Only received signal hav-

ing a matching 3-digit code will open the squelch. q Push [AM/FM] to select FM mode. w Push [MENU] several times to select M1. e Push [F4 TON] several times to turn the DTCS function ON. DTCS appears r Push [F4 TON] for 1 sec. to enter tone frequency set mode. t Push [F1 TON] several times until DTCS Code appears, if necessary. y Rotate the tuning dial to select the desired DTCS code number and push [F5] to select the desired code polarity. NN : Normal polarity is used for both transmit and receive. NR : Normal polarity is used for transmit, reversed polarity is used for receive. RN : Reversed polarity is used for transmit, normal polarity is used for receive. RR : Reversed polarity is used for both transmit and receive. Push [F3] for 1 sec. to select the default code and polar-

ity. u Push [MENU] to return to M1. i Communicate in the usual manner. Available tone codes 023 025 026 031 032 036 043 047 051 053 054 065 071 072 073 074 114 115 116 122 125 131 132 134 143 145 152 155 156 162 165 172 174 205 212 223 225 226 243 244 245 246 251 252 255 261 263 265 266 271 274 306 311 315 325 331 332 343 346 351 356 364 365 371 411 412 413 423 431 432 445 446 452 454 455 462 464 465 466 503 506 516 523 526 532 546 565 606 612 624 627 631 632 654 662 664 703 712 723 731 732 734 743 754 43 I Repeater operation A repeater amplies received signals and retransmits them at a different frequency. When using a repeater, the transmit frequency is shifted from the receive fre-

quency by an offset frequency. A repeater can be ac-

cessed using split frequency operation with the shift frequency set to the repeaters offset frequency. q Push a band key to select the desired band. w Push [A/B] to select VFO A. e Push [AM/FM] to select FM. Pushing [AM/FM] toggles between AM and FM. r Rotate the tuning dial to set the repeater transmit frequency. t While M1 is selected, push [F2 DUP] several times to set the offset direction. DUP or DUP+ appears 0.100 MHz for 50 MHz and 0.600 MHz for 144 MHz band is set by default in set mode. (p. 82) for HF, 0.500 MHz y Push [F4 TON] to turn the repeater tone ON. T appears. Set the tone frequency in tone frequency set mode in advance, if desired. (p. 45) 88.5 Hz is set by default. To transmit a 1750 Hz European repeater tone, push [F4 TON] while transmitting. u Communicate in the normal way. DOne-touch repeater function This function allow you to set repeater operation with push of one switch. To set the transceiver for repeater operation using the one-touch repeater function, follow the steps q to r as above, then push [F2 DUP] for 1 sec. Set the offset shift direction and frequency in ad-

vance (p. 82) as well as the tone frequency (see p. 45). RECEIVE AND TRANSMIT 4 A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Push [F2], [F4]

1 4 5 . O 8 O O O A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Appear A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Push [F2] for 1 sec. 1 4 5 . O 8 O O O A G C D U P C M P T O N S C P F 1 F 2 F 3 F 4 F 5 Appear 44 4 RECEIVE AND TRANSMIT DTransmit frequency monitor check You may be able to receive the other partys transmit signal directly without having to go through a repeater. This function allows you to check this. While receiving, push and hold [XFC] to see if you can receive the other partys transmit signal directly. While holding [XFC], the offset direction and frequency are displayed on the multi-function switch indicator. DRepeater tone frequencies The transceivers repeater tone frequency is set to 88.5 Hz by default. This can be changed if desired. q While M1 is selected, push [F4 TON] to turn the tone encoder ON. T appears. w Push [F4 TON] for 1 sec. to select the tone fre-

quency set mode. e Push [F1 TON] several times to select Rptr Tone, if necessary. r Rotate the tuning dial to select the desired fre-

quency. (see the table at right) t Push [MENU] to return to M1. DStoring a non standard repeater q Turn the auto repeater function OFF in the set mode. (p. 83) w Push [AM/FM] to select FM mode. e Push [V/M], then [A/B] to select VFO A. r Rotate the tuning dial to set the repeater output fre-

quency. Set the tuning step if desired. t Push [A/B] to select VFO B. y Rotate the tuning dial to set the repeater input fre-

quency. u Push [A/B] to select VFO A. i Push [SPLIT] to turn the split function ON. o Push [F4 TON] to turn the previously set tone en-

coder ON.

!0 Rotate [M-CH] to select the desired memory chan-

nel. BLANK appears when blank channel is selected.

!1 Push [MW] for 1 sec. to store the contents in the se-

lected memory channel. 45

[XFC]

- 6 O O . O k A G C D U P C M P T O N S C P R p t r T o n e T O N S C N 8 8 . 5 H z Available tone frequencies

(Unit: Hz) 67.0 69.3 71.9 74.4 77.0 79.7 82.5 085.4 088.5 091.5 094.8 097.4 100.0 103.5 107.2 110.9 114.8 118.8 123.0 127.3 131.8 136.5 141.3 146.2 151.4 156.7 159.8 162.2 165.5 167.9 171.3 173.8 177.3 179.9 183.5 186.2 189.9 192.8 196.6 199.5 203.5 206.5 210.7 218.1 225.7 229.1 233.6 241.8 250.3 254.1

[MW]

[V/M]

[AM/FM] [SPLIT] [A/B] [M-CH]

RECEIVE AND TRANSMIT 4 A u t o R e p e a t e r 1 8 O N - 1 A u t o R e p e a t e r 1 8 O N - 2 A u t o R e p e a t e r 1 8 O F F DAuto repeater function This function automatically activates the repeater set-

tings (DUP or DUP+ and/or tone encoder ON/OFF) when the operating frequency falls within the general repeater output frequency range and deactivates them when outside of the range. Set the auto repeater function ON-1 or ON-2 in set mode in advance (p. 83). When set ON-1 or ON-2, re-

peater settings are automatically activated according to the table below. ON-1 automatically set the duplex setting and ON-2 automatically sets the duplex setting and tone encoder automatically. Frequency range and offset direction FREQUENCY RANGE 145.200145.495 MHz 146.610146.995 MHz 147.000147.395 MHz DUPLEX DIRECTION minus duplex minus duplex plus duplex 46

 

 

5 FUNCTIONS FOR RECEIVE I Simple band scope The band scope function allows you to visually check signal condition around a specied frequency. The IC-

746PROs band scope function can be used in any op-

erating mode and frequency band. S T E P 0 . 5 k Sweep indicator Band scope indicator Frequency indicator mark Sweep step indicator DESCRIPTION INDICATOR Sweep While the band scope is sweeping, audio is not emitted from the speaker while the band scope is sweeping. appears; while stopped appears. Received Band scope in-

dicator Indicates the relative strength of signals and their location in relation to the center (displayed) frequency. Signal strength is relative to the S-meter level, S1 to S9, with each vertical dot in the band scope indicator equal to one segment of the S-meter. Signal activity is measured 30 steps from the center frequency with each step equal to the selected sweep step. Frequency indicator mark After a sweep, indicates the relative position of the selected frequency. When the selected fre-

quency is outside of the sweep range, indicator flashes. After changing the fre-

quency, push [F3] for 1 sec. to automatically return to the center frequency. or Sweep step Indicates the selected sweep step. 0.5, 1, 2, 5, 10, 20 and 25 kHz are selectable. Each dot of the band scope indication is approx. equal to the selected sweep step. The band scope measures receive signal conditions over a specied range on either side of a selected fre-

quency in either VFO or memory modes. q Rotate the tuning dial to tune a frequency. w While M1 is selected, push [F5 SCP] to select the band scope menu. Starts sweeping automatically with the previously se-

lected sweeping step. During sweep, received signals cannot be heard. e Push [F5 STEP] several times to select the desired sweep step. r Push [F1] to start sweeping, then stop automatically after sweeping. Push [F1] for 1 sec. to start continuous sweeping. In this case, it is necessary to push [F1] to stop sweeping. During sweep operation signals cannot be heard. If there is a lot of signal noise, turn the preamp OFF and the attenuator ON to reduce the signal input level and improve the readability of the band scope. appears and received t When rotating the tuning dial and finding a signal you wish to communicate on, simple communicate normally. If you want to return to the previous frequency (before rotating the tuning dial), push [F3] for 1 sec. If the selected frequency is set outside of the sweeped range, or ashes. y While receiving, if you want to update the band con-

ditions, repeat steps e and r as above. 47 S T E P O . 5 k F 1 F 2 F 3 F 4 F 5 Sweep start/stop Sweep step selection S T E P O . 5 k F 1 F 2 F 3 F 4 F 5 Sweep indicator I Preamp/Attenuator The preamp amplies received signals in the front end circuit to improve the S/N ratio and sensitivity. Set this to preamp 1 or preamp 2 when receiving weak signals. The attenuator prevents a desired signal from distor-

tion when very strong signals are near the desired fre-

quency or when very storing electric fields, such as from broadcasting station, are near your location. These can both set independently for each band. Push [P.AMP/ATT] several times to set the preamp OFF, preamp 1 ON or preamp 2 ON. When the preamp is ON, either P.AMP 1 or P.AMP 2 appears in the function display. When operating on the 144 MHz band, the preamp can only be set to ON or OFF only there is no preamp 1 and preamp 2. Regular preamp, the most effective for 1.8 to 21 MHz bands without IMD corruption. High-gain preamp, the most effective for 24 to 50 MHz bands. Preamp activates for the VHF band (144 to 146 MHz range; 108 to 174 for the USA version). Push [P.AMP/ATT] for 1 sec. to set the attenuator ON. ATT appears ni the display when the function is set ON. Push [P.AMP/ATT] momentarily to set the attenuator OFF. Regarding the use of the P.AMP 2 The P.AMP 2 is a high gain receive amplier. When the P.AMP 2 is used during times of strong electric elds, dis-

tortion sometimes results. In such cases, use the trans-

ceiver with the P.AMP 1 or P.AMP OFF setting. I RIT function The RIT (Receive Increment Tuning) function compen-

sates for off-frequencies of the communicating station. The function shifts the receive frequency up to 9.99 kHz in 10 Hz steps without moving the transmit frequency. See #0 on p. 4 for function description. q Push [RIT] to turn the RIT function ON and OFF. RIT and the shifting frequency appear when the func-

tion is ON. w Rotate the [RIT/TX] control. Push [CLEAR] for 1 sec. to reset the RIT frequency. Push [CLEAR] momentarily to reset the RIT frequency when the quick RIT/TX clear function is ON. (p. 85) Push [RIT] for 1 sec. to add the shift frequency to the op-

erating frequency. DRIT monitor function When the RIT function is ON, pushing and holding

[XFC] allows you to monitor the operating frequency directly (RIT is temporarily cancelled). FUNCTIONS FOR RECEIVE 5

[P.AMP/ATT]

Push Push P.AMP/ATT P.AMP/ATT Push P.AMP/ATT Push Push for 1sec. P.AMP/ATT P.AMP/ATT The P.AMP 2 is most effective when:

Used on bands above 24 MHz and when electric elds are weak. Receive sensitivity is insufcient during low gain, or while using a narrow band antenna (such as small loop, a Bever-

age antenna or a short Yagi antenna, etc.) is used.

[CLEAR]

[RIT]

[RIT/TX] control appear 48 5 FUNCTIONS FOR RECEIVE I AGC function The AGC (auto gain control) controls receiver gain to produce a constant audio output level even when the received signal strength is varied by fading, etc. The transceiver has 3 AGC characteristics (time con-

stant; fast, mid, slow) for non-FM mode. The FM mode AGC time constant is xed as FAST

(0.1 sec.) and AGC time constant cannot be se-

lected. DAGC speed selection q Select non-FM mode. w While M1 is selected, push [F1 AGC] several times to select AGC F, AGC M, AGC S or AGC OFF. AGC OFF appears when AGC time constant OFF is set with one of FAST, MID or SLOW setting in AGC set mode. DSetting the AGC time constant q Select the desired mode except FM mode. w While M1 is selected, push [F1 AGC] for 1 sec. to enter AGC set mode. e Push one of [F2 FAST], [F3 MID] or [F4 SLOW] to se-

lect the desired AGC speed to be set. Underline appears below the time constant indication. r Rotate the tuning dial to set the desired time con-

stant. AGC time constant can be set between 0.1 to 8.0 sec.

(depends on mode) or turned OFF. Push [F2 FAST], [F3 MID] or [F4 SLOW] for 1 sec. to se-

lect a default value for each fast, mid. and slow, respec-

tively. t Select another mode except FM. Repeat steps e and r if desired. y Push [MENU] to exit the AGC set mode. Selectable AGC time constant

(unit: sec.) Mode Default 0.3 (FAST) SSB 2.0 (MID) 6.0 (SLOW) 0.1 (FAST) CW 0.5 (MID) 1.2 (SLOW) 0.1 (FAST) RTTY 0.5 (MID) 1.2 (SLOW) 3.0 (FAST) AM 5.0 (MID) 7.0 (SLOW) Selectable AGC time constant OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6 2.0, 2.5, 3.0, 4.0, 5.0, 6.0 OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6 2.0, 2.5, 3.0, 4.0, 5.0, 6.0 OFF, 0.1, 0.2, 0.3, 0.5, 0.8, 1.2, 1.6 2.0, 2.5, 3.0, 4.0, 5.0, 6.0 OFF, 0.3, 0.5, 0.8, 1.2, 1.6, 2.0, 2.5 3.0, 4.0, 5.0, 6.0, 7.0, 8.0 FM 0.1 (FAST) Fixed 49

[F1 AGC] Mode switches

: Medium AGC speed

: Slow AGC speed

: Fast AGC speed

: AGC does not activated A G C D U P C M P T B W S C P F 1 F 2 F 3 F 4 F 5 Push [F1] for 1 sec. F 1 F 2 F 3 F 4 F 5 Appears under the selected AGC speeds time constant indication. Selected mode When AGC fast is selected F 1 F 2 F 3 F 4 F 5 Push [F2] for 1 sec. to select the default value in this case. I IF lter selection The transceiver has 3 passband width IF filters for each mode. For SSB and CW modes, the passband width can be set within 50 to 3600 Hz in 50 or 100 Hz steps. A total of 41 passband widths are available. For RTTY mode, the passband width can be set within 50 to 2700 Hz in 50 or 100 Hz steps. A total of 32 passband widths are available. For AM and FM modes, the passband width is fixed and 3 passband widths are available independently. The filter selection is automatically memorized in each mode. The PBT shift frequencies are automatically memo-

rized in each lter. DIF lter selection q Select the desired mode. w For RTTY mode, turn OFF the RTTY lter. e Push [FILTER] several times to select the IF filter 1, 2 or 3. The selected passband width and filter number is dis-

played in the LCD. By pushing [PBTC] indicate the set lter passband width, B, and shifting value S. FUNCTIONS FOR RECEIVE 5

[FILTER]

A G C D U P C M P T B W S C P The selected filter width is indicated for approx. 1 sec. when [FILTER] is pushed. Filter selection DFilter passband width setting (SSB, CW and RTTY mode only) q Select SSB, CW or RTTY mode. Filter set mode indication Passband widths for AM and FM modes are fixed and cannot be set. w For RTTY mode, turn OFF the RTTY lter. e Push [FILTER] for 1 sec. to enter lter set mode. r Push [FILTER] several times to select the desired IF lter number. t While pushing [F1 BW], rotate the tuning dial to set the desired passband width. In SSB and CW modes, the passband width can be set within the following range. 50 to 500 Hz 600 to 3600 Hz 50 Hz steps 100 Hz steps In RTTY mode, the passband width can be set within the following range. 50 to 500 Hz 600 to 2700 Hz 50 Hz steps 100 Hz steps Push [F-3] for 1 sec. to select the default value. y Repeat steps r to t if desired. u Push [MENU] to exit the lter set mode. The PBT shift frequencies are cleared when the passband width is changed. This lter set mode screen graphically displays the PBT shift frequencies and CW pitch operations. B W Shows the selected filter and passband width. Indication while setting B W Reverses Appears While pushing [F1 BW], rotate the tuning dial to set passband width. 50 5 FUNCTIONS FOR RECEIVE I IF (DSP) lter shape The type of IF (DSP) filter shape for each SSB and CW can be selected independently from soft and sharp. q Push [SSB] or [CW/RTTY] to select SSB, CW or RTTY mode. w Select the lter set mode. Push [FILTER] for 1 sec. Operating mode can be selected in this step. e Push [FILTER] several times to select the desired IF lter. r Push the [F5] to select the lter shape from SOFT and SHARP. t Push [MENU] to exit the set mode. I Noise blanker The noise blanker eliminates pulse-type noise such as from car ignitions. The noise blanker is not available for FM mode. q Push [NB] to turn the noise blanker ON.

[NB] indicator appears. w Push [NB] for 1 sec. to enter the NB level set mode. e Rotate the tuning dial to adjust the noise blanker level. Noise blanker level is indicated with bar meter and digit in %. r Push [NB] to exit the noise blanker set mode. t Push [NB] to turn the noise blanker OFF.

[NB] indicator disappears. B W B W Push [F5]

[NB]

NB appears while noise blanker is activated. N B L e v e l 5 O %

When using the noise blanker, received signals may be distorted if they are excessively strong. Shows noise blanker level I Meter peak hold function The S-meter shows the peak level holding function. Peak level of receiving signal strength is indicated for 0.5 sec. (approx.). This function can be deactivated in the set mode if desired. (p. 81) 51 M e t e r P e a k H o l d 9 O N Shows peak level for approx. 0.5 sec. I Twin PBT operation General PBT (Passband Tuning) function electronically narrows the IF passband width by shifting the IF fre-

quency to slightly outside of the IF lter passband to reject interference. This transceiver uses the DSP cir-

cuit for the PBT function. Moving both [TWIN PBT]

controls to the same position shifts the IF. The LCD shows the passband width and shift fre-

quency graphically. Push [FILTER] for 1 sec. to enter the lter set mode. Current passband width and shift frequency is dis-

played in the lter set mode screen. To set the [TWIN PBT] controls to the center posi-

tions, push [PBTC] for 1 sec. The variable range depends on the passband width and mode. The edge of the variable range is half of the passband width, and PBT is adjustable in 25 or 50 Hz steps. These controls function as an IF shift control while in AM mode and when the RTTY lter is turned ON. Only the inner control may function in this case. IF shift is adjustable in 20/40 Hz steps in RTTY (RTTY lter is turned ON) or 150/300/500 Hz steps in AM.

[TWIN PBT] should normally be set to the center posi-

tions (PBT setting is cleared) when there is no interfer-

ence. When PBT is used, the audio tone may be changed. Not available for FM mode. For AM and RTTY (with RTTY filter ON) modes,

[TWIN PBT] inner control can only be activated, and functions as an IF shift function. While rotating [TWIN PBT], noise may occur. This comes from the DSP unit and does not indicate an equipment malfunction. By pushing [PBTC] momentarily, indicate the using lter passband width, B, and shifting value, S. FUNCTIONS FOR RECEIVE 5

[TWIN PBT] control

[PBTC]

A G C D U P C M P T B W S C P Passband width and shifting value are indicated while [TWIN PBT] is operated. Appears when PBT is used. Filter set mode indication B W Shows the selected filter and passband width. Indication while PBT setting B W Appears when passband is shifted.

*Pushing [PBTC] for 1 sec., the shifted value return to default setting and the dot disappears. PBT OPERATION EXAMPLE Center Passband Passband IF shift pass band IF center frequency interference desired signal inteference desired signal IF center freq. interference 52 5 FUNCTIONS FOR RECEIVE I Noise reduction The noise reduction function reduces noise compo-

nents and picks out desired signals which are buried in noise. The received signals are converted to digital signals and then the desired signals are separated from the noise. q Push the [NR] switch to turn the noise reduction ON. NR appears. w Rotate the [NR] control to adjust the noise reduction level. e Push the [NR] switch to turn the noise reduction OFF. NR disappears. Deep rotation of the [NR] control results in audio sig-

nal masking or distortion. Set the [NR] control for maximum readability. I Notch function This transceiver has auto and manual notch functions. The auto notch function automatically attenuates more than 3 beat tones, tuning signals, etc., even if they are moving. The manual notch can be set to attenuate a frequency via the [NOTCH] control. Push [A/NOTCH] to toggle the notch function be-

tween auto, manual and OFF in SSB and AM modes. Push [A/NOTCH] to turn the manual notch function ON and OFF in CW mode. Push [A/NOTCH] to turn the auto notch function ON and OFF in FM mode. Set to attenuate a frequency for manual notch via the

[NOTCH] control. A NOTCH appears when auto notch is in use. NOTCH appears when manual notch is in use. While operating the manual notch, noise may be heard. This comes from the DSP unit and does not indicate an equipment malfunction. I Dial lock function The dial lock function prevents accidental changes caused by the tuning dial. Push [LOCK/SPCH] to turn the dial lock function ON and OFF. LOCK indicator lights while the dial lock function is ac-

tivated.

[NR]

[NR]

A G C D U P C M P T B W S C P Appears

[A/NOTCH]

[NOTCH]

A G C D U P C M P T B W S C P Notch function indicators Lights while the dial lock function is activated. 53

[LOCK/SPCH]

I Voice squelch control function This function is useful when you dont want unmodu-

lated signals. When the voice squelch control function is activated, the receiver checks received signals for voice components. If a receiver signal includes voice components, and the tone of the voice components changes within 1 sec., squelch opens. If the received signal includes no voice components or the tone of the voice components does not change within 1 sec., squelch closes. While M2 is selected with [MENU], push [F5 VSC]

to switch the VSC (Voice Squelch Control) function ON and OFF. VSC appears when the function is activated. The VSC function activates for phone modes

(SSB, AM and FM). The VSC function can also be used for scanning operation in AM or FM mode (p. 00). FUNCTIONS FOR RECEIVE 5 VSC indicator S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F5] to turn the VSC function ON and OFF. 54 6 FUNCTIONS FOR TRANSMIT I VOX function The VOX (Voice-Operated Transmission) function switches between transmit and receive with your voice. This function provides an opportunity to input log en-

tries into your computer, etc., while operating. Using the VOX function q Select a phone mode (SSB, AM, FM). w Push [VOX/BK-IN] to turn the VOX function ON or OFF. DAdjusting the VOX function q Select a phone mode (SSB, AM, FM). w Push [VOX/BK-IN] to turn VOX function ON. e Push [VOX/BK-IN] for 1 sec. to enter VOX set mode. r Select the VOX Gain item using [F1 ] or [F2 ]. t While speaking into the microphone, rotate the tun-

ing dial to the point where the transceiver is contin-

uously transmitting.

- Pushing [F3] for 1 sec. to select the default value. y Push [F2 ] to select Anti-VOX item. u While receiving, rotate the tuning dial to the point where the transceiver does not switch to transmit with the speaker output.

- Pushing [F3] for 1 sec. to select the default value. y Push [F2 ] to select VOX Delay item. y Adjust the VOX delay for a convenient interval be-

fore returning to receive.

- Select the VOX delay item using the tuning dial.

- Pushing [F3] to select the default value. u Push [MENU] to return to previous indication.

[VOX/BK-IN]

A G C D U P C M P T B W S C P Appears V O X G a i n 1 5 O %

F 1 F 2 F 3 F 4 F 5 Shows VOX gain level A n t i - V O X 2 5 O %

F 1 F 2 F 3 F 4 F 5 Shows anti-VOX gain level V O X D e l a y 3 O . 2 s F 1 F 2 F 3 F 4 F 5 Shows VOX delay time 55 I Break-in function The break-in function is used in CW mode to automat-

ically toggle the transceiver between transmit and re-

ceive when keying. The IC-746PRO is capable for full break-in or semi break-in. DSemi break-in operation During semi break-in operation, the transceiver selects transceive when keying, then automatically returns to receive after a pre-set time from when you stop keying. q Push [CW/RTTY] to select CW or CW-R mode. w Push [VOX/BK-IN] several times to turn the semi break-in function ON. BK-IN appears. e Set the break-in delay time (the delay from transmit to receive). Push [VOX/BK-IN] for 1 sec. to select break-in delay program mode. Rotate the tuning dial to select the desired delay. Push [F3] for 1 sec. to select to the default value. r Push [MENU] to return to the previous menu. When using a paddle, rotate [KEY SPEED] to adjust the keying speed. DFull break-in operation During full break-in operation, the transceiver automati-

cally selects receive if a signal is detected while keying. q Push [CW/RTTY] to select CW or CW-R mode. w Push [VOX/BK-IN] several times to turn the full break-in function ON. FBK-IN appears. When using a paddle, rotate [KEY SPEED] to adjust the keying speed. FUNCTIONS FOR TRANSMIT 6

[VOX/BK-IN]

B r e a k - I N D e l a y 7 . 5 d Break-in indicator Shows break-in delay time A G C D U P 1 / 4 K E Y S C P Full break-in indicator 56 6 FUNCTIONS FOR TRANSMIT I TX function The TX function shifts the transmit frequency up to 9.99 kHz in 10 Hz steps without moving the receive frequency. See #2 on p. 4 for function description. q Push the [TX] switch to turn the TX function ON and OFF. TX and shift frequency appear when the function is ON. w Rotate the [RIT/TX] control. To reset the TX frequency, push [CLEAR] for 1 sec. Push [CLEAR] momentarily to reset the RIT frequency when the quick RIT/TX clear function is ON. (p. 00) To add or subtract the TX frequency to the displayed frequency, push [TX] for 1 sec. When RIT and TX are ON at the same time, the

[RIT/TX] control shifts both the transmit and re-

ceive frequencies from the displayed frequency at the same time. D TX monitor function When the TX function is ON, pushing and holding

[XFC] allows you to monitor the operating frequency di-

rectly (TX is temporarily cancelled). I Monitor function The monitor function allows you to monitor your trans-

mit IF signals in any mode through the speaker. Use this to check voice characteristics while adjusting SSB transmit tones. (p. 88) The CW sidetone functions re-

gardless of the [MONITOR] switch setting. q Push [MONITOR] to switch the monitor function ON and OFF. MONI appears when the monitor function is ON. w Set the monitor level. Push [MONITOR] for 1 sec. to select monitor pro-

gram mode. Rotate the tuning dial for the clearest audio out-

put while pushing [PTT] and speaking into the mi-

crophone. Push [F3] for 1 sec. to select the default value. r Push [MENU] to return to the previous menu.

[CLEAR]

[TX]

[RIT/TX] control appear

[MONITOR]

M O N I T O R L e v e l 5 O %

Monitor indicator Shows monitor level 57 I Speech compressor The speech compressor increases average RF output power, improving signal strength and readability in SSB, AM or FM. When adjusting the compression level, it is necessary to turn the COMP meter ON in the set mode, in ad-

vance (p. 81). In SSB mode q Select USB or LSB mode and adjust [MIC GAIN] to a suitable level. w While M1 is selected, push [F3 CMP] to turn the speech compressor ON. COMP appears. e Push [F3 CMP] for 1 sec. to select compression level set mode. r While speaking into the microphone, rotate the tun-

ing dial, so that the COMP meter reads within the COMP zone with your normal voice level. Push [F3] for 1 sec. to select the default value. When the COMP meter peaks above the COMP zone, your transmitted voice may be distorted. t Push [MENU] to return to M1. In AM/FM mode q While M1 is selected, push [F3 CMP] to turn the speech compressor ON. COMP appears. w Push [F3 CMP] for 1 sec. and set the compression level as 1 in advance. e While speaking into the microphone, rotate [MIC GAIN], so that the COMP meter does not exceeds the center dot whether you speak softly or loudly. r While speaking into the microphone, rotate the tun-

ing dial, so that the COMP meter reads within the COMP zone with your normal voice level. Push [F3] for 1 sec. to select the default value. When the COMP meter peaks above the COMP zone, your transmitted voice may be distorted. t Push [MENU] to return to M1. FUNCTIONS FOR TRANSMIT 6 C O M P L e v e l Compressor indicator Shows compression level ALC meter COMP meter COMP level zone

*The SWR meter functions as the COMP meter when COMP meter is set to ON in the set mode. C O M P L e v e l 5 1 Adjust [MIC GAIN], so that the COMP meter does not exceeds this zone. Adjust the COMP Level with the tuning dial so that the COMP meter does not exceeds the COMP level zone. I Transmit lter width selection (SSB mode only) The transmit lter width for SSB mode can be selected from wide, middle and narrow. A G C D U P C M P T B W S C P q Select USB or LSB mode. w Push [MENU] to select M1, if necessary. e Push [F4 TBW] for 1 sec. to select the transmission passband width. One of TX BW=WIDE, TX BW=MID or TX BW=NAR is displayed for approx. 1 sec. Transmit lter width: NAR MID WIDE 2.0 kHz 2.6 kHz 2.9 kHz F 1 F 2 F 3 F 4 F 5 Push [F4]

T X B W = W I D E A G C D U P C M P T B W S C P F 1 F 2 F 3 F 4 F 5 The selected transmit filter width is displayed for approx. 1 sec. Push [F4] for 1 sec. to select the transmit filter width. 58 6 FUNCTIONS FOR TRANSMIT I Split frequency operation Split frequency operation allows you to transmit and receive in the same mode on two different frequencies. The split frequency operation is basically performed using 2 frequencies in VFO A and VFO B. The following is an example of setting 21.290 MHz for receiving and 21.310 MHz for transmitting. q Set 21.290 MHz (USB) in VFO A. w Push [SPLIT] to turn the split function ON, then push [A/B] for 1 sec. The equalized transmit (VFO B) frequency and SPLIT appear on the LCD, and the [SPLIT] indicator lights. e While pushing [XFC] rotate the tuning dial to set the transmit frequency to 21.310 MHz. The transmit frequency can be monitored while pushing

[XFC]. r Now you can receive on 21.290 MHz and transmit on 21.310 MHz. To change the transmit and receive frequencies, push

[A/B] to exchange the VFO A and VFO B.

[SPLIT] Lights during split operation

[XFC]

Tuning dial

[A/B]

2 1 . 2 9 O O O A G C D U P C M P T B W S C P Shows transmit (VFO B) frequency Appears CONVENIENT While pushing [XFC]

Direct shift frequency input The shift frequency can be entered directly. q Push [F-INP]. w Enter the desired shift frequency with the digit keys. 1 kHz to 1 MHz can be set. When you require a minus shift direction, push

[GENE ] in advance. e Push [SPLIT]. The shift frequency is input in the sub readout and the split function is turned ON.

[Example]

To transmit on 1 kHz higher frequency:

- Push [F-INP], [1.8 1] then [SPLIT]. To transmit on 3 kHz lower frequency:

- Push [F-INP], [GENE ], [7 3] then [SPLIT]. Split lock function Accidentally releasing the [XFC] switch while rotating the tuning dial changes the receive frequency. To pre-

vent this, use both the split lock and dial lock func-

tions to change the transmit frequency only. The split lock function cancels the dial lock function while pushing [XFC] during split frequency operation. The dial locks effectiveness during split frequency operation can be selected in the set mode for both receive and transmit frequencies; or only the receive frequency. (p. 82) 59

+ 2 O . O O k A G C D U P C M P T B W S C P Shows shift frequency and direction Shows transmit (VFO B) frequency After setting up 2 1 . 3 1 O O O A G C D U P C M P T B W S C P I Quick split function When you push the [SPLIT] switch for 1 sec., split fre-

quency operation is turned ON, the un-displayed VFO is automatically changed according to the plus/minus shift frequency programmed in set mode (p. 82) or equalized when 0 kHz (default value) is programmed as the split shift frequency. Quick split operation is turned ON by default but can be turned OFF in set mode (p. 82). q Suppose you are operating at 21.290 MHz (USB) in VFO A. w Push [SPLIT] for 1 sec. Split frequency operation is turned ON. The VFO and VFO B are equalized. e While pushing [XFC], rotate the tuning dial to set the frequency offset between transmit and receive. When [XFC] is released, the receive frequency is indi-

cated. DSplit offset frequency setting By setting an often-used split frequency offset in ad-

vance, you can use the quick split function to select split operation at the push of one switch. Set the split offset frequency in advance in set mode

(p. 82, item 12). The example at right shows the split offset is set to +0.020 MHz. Push [SPLIT] for 1 sec. to activate the quick split function. The transmit frequency is offset from the receive fre-

quency according to the offset in set mode. DSplit lock function The split lock function is convenient for changing only the transmit frequency. When the split lock function is not used, accidentally releasing [XFC] while rotating the tuning dial, changes the receive frequency. The split lock function is ON by default, but can be turned OFF in set mode. q While split frequency operation is ON, push

[LOCK/SPCH] to activate the split lock function. w While pushing [XFC], rotate the tuning dial to change the transmit frequency. If you accidentally release [XFC] while rotating the tuning dial, the receive frequency does NOT change. FUNCTIONS FOR TRANSMIT 6 Setting the frqeuency while pushing [XFC]

+ 2 O . O O k A G C D U P C M P T B W S C P Shows shift frequency and direction S P L I T O f f s e t 1 2

+ O . O 2 O M H z 2 1 . 3 1 O O O A G C D U P C M P T B W S C P Shows transmit frqeuency for split operation S P L I T L O C K 1 3 O F F

[XFC]

Tuning dial

[LOCK/SPCH]

60 6 FUNCTIONS FOR TRANSMIT I Measuring SWR The IC-746PRO has a built-in circuit for measuring an-

tenna SWR no external equipment or special adjust-

ments are necessary. The IC-746PRO can measure SWR in 2 ways spot measurement and plot measurement are available. DSpot measurement q Push [TUNER] to turn the antenna tuner OFF. w Turn the COMP meter OFF. Push [MENU] for 1 sec. to enter set mode. Push [F1 ] or [F2 ] several times to select the COMP Meter item. Rotate the tuning dial to set the COMP meter OFF. Push [MENU] to exit set mode. e Push [CW/RTTY] several times to select RTTY mode. r Push [TRANSMIT] or [PTT] of the microphone. t Rotate [RF PWR] clockwise past the 12 oclock po-

sition for more than 30 W output power (30%). y Read the SWR on the SWR meter. u Push [TRANSMIT] or release [PTT] to receive. The built-in antenna tuner matches the transmitter to the antenna when the SWR is lower than 3:1. DPlot measurement Plot measurement allows you to measure the SWR over an entire band. q While M2 is selected with [MENU], push [F3 SWR]. SWR graph screen appears. w Rotate [RF PWR] clockwise past the 12 oclock po-

sition for more than 30 W output power (30%). e Set the center frequency for the SWR to be mea-

sured. r Push [F5] for 1 sec. several times to select the de-

sired measuring step from 10, 50, 100 and 500 kHz. t Push [F3] several times to select the desired num-

ber of measuring steps from 3, 5, 7, 9, 11 and 13 steps. y Push [F1] to start the measuring. u Push [TRANSMIT] or push and hold [PTT] of the microphone to measure the SWR. Frequency marker, , appears below SWR graph. RTTY mode is automatically selected. i When pushing [TRANSMIT] again or release [PTT], the frequency marker and frequency indication move to the next frequency to be measured. o Repeat steps u and i to measure SWR over the entire frequency range.

!0 When the measured SWR is less than 1.5:1, the antenna is well matched with the transceiver in the measured frequency range. 61 A G C D U P 1 / 4 R T Y S C P The best match is in this range. S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F3]

S T E P 1 O k F 1 F 2 F 3 F 4 F 5 Push [F1] to start measuring. Push [F3] to select number of SWR measuring steps. Push [F5] to select SWR measuring step. Measuring (after pushing [F1]) S T E P 1 O k Frequency marker appears and moves after meas-

urement.

*When mesurement point/s is/are set outside of the oper-

atable frequency band, frequency marker flashes. 4.0:1 3.0:1 2.0:1 1.5:1 1.0:1 Typical display SWR varying between 1 and 2, full scale up to SWR 4.0:1. MEMORY OPERATION 7 I Memory channels The transceiver has 101 memory channels (plus 1 call channel). The memory mode is very useful for quickly changing to often-used frequencies. All 101 memory channels are tuneable which means the programmed frequency can be tuned temporarily with the tuning dial, etc. in memory mode. MEMORY CHANNEL Regular memory channels Scan edge memory channels MEMORY CHANNEL NUMBER 199 P1, P2 Call channel C CAPABILITY TRANSFER TO VFO OVER-

WRITING CLEAR One frequency and one mode in each memory channel. One frequency and one mode in each memory channel as scan edges for programmed scan. Same as regular. Yes Yes No Yes Yes Yes Yes No No I Memory channel selection DIn VFO mode q Push [V/M] to select VFO mode, if necessary, then rotate [M-CH] to select a memory channel number. All memory channels including blank channels can be selected. BLANK appears when no information has been pro-

grammed into a memory channel. w Push [V/M] to select memory mode. MEMO and contents of the memory channel appear. DIn memory mode q Push [V/M] to select memory mode. w Rotate [M-CH] to select a memory channel. All memory channels including blank channels can be selected. Memory channels can also be selected using the micro-

phone [UP]/[DN] keys. During VFO mode

[V/M]

[M-CH]

Disappears when a channel is programmed. During memory mode 62 7 MEMORY OPERATION I Programming a memory Memory channel programming can be preformed ei-

ther in VFO mode or in memory mode. DProgramming in VFO mode q Set the desired frequency and operating mode in VFO mode. w Rotate [M-CH] to select the desired memory chan-

nel. BLANK appears if the selected memory channel is a blank channel (and does not have contents). e Push [MW] for 1 sec. to program the displayed fre-

quency and operating mode into the memory chan-

nel. 3 beeps are emitted when memory programming is suc-

cessful. DProgramming in VFO mode q Select the desired memory channel with [M-CH] in memory mode. Memory channel contents appear in the display. BLANK appears and no frequency readout is displayed if the selected memory channel is a blank channel (and does not have contents). w Set the desired frequency and operating mode in memory mode. To program a blank channel, use direct frequency entry with the keypad or memo pads, etc. e Push [MW] for 1 sec. to program the displayed fre-

quency and operating mode into the memory chan-

nel. 3 beeps are emitted when memory programming is suc-

cessful. I Memory clearing Any unnecessary memory channels can be cleared. The cleared memory channels become blank chan-

nels. q Select memory mode with [V/M]. w Select the desired memory channel with [M-CH]. e Push [M-CL] for 1 sec. to clear the contents. The programmed frequency and operating mode disap-

pear. 3 beeps are emitted when memory clearing is success-

ful. r To clear other memory channels, repeat steps w and e. 63

[MW]

[V/M]

[M-CH]

[EXAMPLE]: Programming 7.088 MHz/LSB into memory channel 12. A G C D U P C M P T B W S C P

[EXAMPLE]: Programming 21.280 MHz/USB into memory channel 18. A G C D U P C M P T B W S C P

[M-CL]

[V/M]

[M-CH]

I Selecting the call channel By default 145.00000 MHz/FM is programmed into the call channel. However, this can be changed to suit your operating preference. (see below) q Push [CALL] to select the call channel. C appears. w Push [CALL] again to return to the previous mode. MEMORY OPERATION 7

[CALL]

I Programming the call channel The call channel is programmed in the same way reg-

ular memory channels are. Its convenient to program a most-often-used frequency into the call channel for quick recall. As with memory channels, the call chan-

nel can also hold split frequencies. q Rotate [M-CH] to select the call channel. C appears. w Select the desired frequency and operating mode to program into the call channel. e Push [MW] for 1 sec. to program the displayed fre-

quency and operating mode into the call channel. 3 beeps are emitted when memory programming is suc-

cessful. IMPORTANT!: When the call channel is selected with the [CALL] switch, the frequency CANNOT be changed using the tuning dial, band keys or keypad input. However, when the call channel is selected using [M-CH] in memory mode, the frequency CAN be changed. A G C D U P C M P T O N S C P C appears

[MW]

[V/M]

[M-CH]

A G C D U P C M P T O N S C P 64 7 MEMORY OPERATION I Frequency transferring The contents of a memory channel (frequency, oper-

ating mode, etc.) can be transferred to the VFO. Frequency transferring can be performed in either VFO mode or memory mode. DTransferring in VFO mode This is useful for transferring programmed contents to VFO. q Select VFO mode with [V/M]. w Select the memory channel to be transferred with

[M-CH]. BLANK appears if the selected memory channel is a blank channel. In this case transferring is impossible. e Push [V/M] for 1 sec. to transfer the frequency and operating mode. 3 beeps are emitted. DTransferring in memory mode This is useful for transferring frequency and operating mode while operating in memory mode. When you have changed the frequency or operat-

ing mode in the selected memory channel:

Displayed frequency and mode are transferred. Programmed frequency and mode in the memory channel are not transferred, and they remain in the memory channel. q Select the memory channel to be transferred with

[M-CH] in memory mode. And, set the frequency or operating mode if required. w Push [V/M] for 1 sec. to transfer the frequency and operating mode. 3 beeps are emitted when the transferring is successful. Displayed frequency and operating mode are transferred to the VFO. e To return to VFO mode, push [V/M] momentarily. 65

[V/M]

[M-CH]

TRANSFERRING EXAMPLE IN VFO MODE Operating frequency : 21.320 MHz/USB (VFO) Contents of M-ch 16 : 14.018 MHz/CW Push [V/M] for 1 sec. TRANSFERRING EXAMPLE IN MEMORY MODE Operating frequency : 14.020 MHz/CW (M-ch 16) Contents of M-ch 16 : 14.018 MHz/CW Set the frquency Push [V/M] for 1 sec. then push [V/M]

MEMORY OPERATION 7

[V/M]

[MW]

Tuning dial [M-CH]

After steps w to r After steps t to u I Programming scan edges Memory channels P1 and P2 are the program scan edges. They are used to program an upper and lower frequency for programmed scan (p. 71). By default, P1 is programmed with 0.50000 MHz and P2 is pro-

grammed with 29.99999 MHz. If P1 and P2 are pro-

grammed with the same frequencies, programmed scan will not proceed.

[EXAMPLE]: Programming 14.00000 MHz into P1 and 14.35000 MHz into P2. q Push [V/M] to select VFO mode, if necessary. w Rotate [M-CH] to select scan edge P1. e Rotate the tuning dial to set 14.00000 MHz as the lower frequency. r Push [MW] for 1 sec. to program 14.00000 MHz into scan edge P1. 3 beeps are emitted. t Rotate [M-CH] to select scan edge P2. y Rotate the tuning dial to set 14.35000 MHz as the upper frequency. u Push [MW] for 1 sec. to program 14.35000 MHz into scan edge P2. 3 beeps are emitted. When programmed scan is activated (p. 71) scanning will search the frequencies between 14.00000 MHz and 14.35000 MHz for signals. 66 7 MEMORY OPERATION I Assigning memory names All memory channels (including scan edges) can be tagged with alphanumeric names of up to 9 characters each.

[EXAMPLE]: Programming DX spot into memory channel 99. q Push [V/M] to select memory mode, if necessary. w Rotate [M-CH] to select memory channel 99. e Push [MENU] several times to select M2. r Push [F2 MEM] to select the memory name screen. t Push [F1 EDT] to edit memory channel name. A cursor appears and blinks. Memory channel names of blank channels cannot be edited. y Push [F1] several times to select the type of char-

acters for input. ABC inputs capital letters A to Z. abc inputs small letters a to z. etc is used to input other characters ! # $ % & ?

` ^ + , / . , : ; = < > ( ) [ ] { } | _ are available. Use the keypad to directly input numerals, 0 to 9, in-

cluding a decimal point. u Rotate the tuning dial to select the rst character for input. i Push [F2 ] or [F3 ] to move the cursor forwards or backwards, respectively. Push [F5 SPC] to input a space and [F4 DEL] to delete the selected character. o Repeat steps w to i to program another memory channels name, if desired.

!0 Push [MENU] to set the memory channel name and return to the memory name menu. Push [MENU] 1 more times to return to M2. 67

[V/M]

[MENU]

Tuning dial [M-CH]

S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F2 MEM]

1 4 . 1 9 5 O O U S B E D T ( ) S E L F 1 F 2 F 3 F 4 F 5 Push [F2 MEM]

A B C D E L S P C F 1 F 2 F 3 F 4 F 5 During assigning a memory names D X A B C D E L S P C F 1 F 2 F 3 F 4 F 5 Input space Delete a character Move cursor forwards Move cursor backwards Selects character type After assigning a memory names D X s p o t a b c D E L S P C F 1 F 2 F 3 F 4 F 5 MEMORY OPERATION 7 NOTE: Each memo pad must have its own unique combination of frequency and operating mode;

memo pads having identical settings cannot be writ-

ten. Stored in next available memo pad I Memo pads The transceiver has a memo pad function to store fre-

quency and operating mode for easy write and recall. The memo pads are separate from memory channels. The default number of memo pads is 5, however, this can be increased to 10 in set mode if desired. (p. 84) DWriting frequencies and operating modes into memo pads Push [MP-W] to store the displayed frequency and operating mode into a memo pad. Each push of [MP-W] stores a frequency and mode into the next available memo pad; when you write a 6the (or 11the) frequency and operating mode, the oldest written frequency and operating mode are automatically erased to make room for the new settings. Displayed frequency and mode MP-W A G C D U P C M P T B W S C P In this example, pushing [MP-W] enters 21.28000 MHz USB into the top memo pad and erases the oldest memo pad (21.34724 MHz LSB). DRecalling a memo pad Push [MP-R] to recall a memo pad. Each push of [MP-R] recalls a memo pad, starting from the most recently written. VFO or memory mode Memo pads Erased A G C D U P C M P T B W S C P MP-R MP-R 68 7 SCANS I Scan types PROGRAMMED SCAN Repeatedly scans between two scan edge frequencies

(scan edge memory channels P1 and P2). F SCAN Repeatedly scans within F span area. Scan edge P1 or P2 Scan edge P2 or P1 F frequency

+F frequency Start frequency Scan Jump Scan Scan Jump This scan operates in VFO mode. This scan operates in both VFO and memory modes. MEMORY SCAN Repeatedly scans all programmed memory channels. SELECT MEMORY SCAN Repeatedly scans all select memory channels. Mch 2 SEL Mch 3 Mch 4 Mch 2 SEL Mch 3 Mch 4 Mch 1 SEL SEL Mch 5 Mch 1 SEL SEL Mch 5 Mch 99 SEL Mch 7 SEL Mch 6 Mch 99 SEL Mch 7 SEL Mch 6 This scan operates in memory mode. This scan operates in memory mode. I Preparation Channels For programmed scan:

Program scan edge frequencies into scan edge mem-

ory channels P1 and P2. For Fscan:

Set the F span (F scan range) in the scan screen. For memory scan:

Program 2 or more memory channels except scan edge memory channels. For select memory scan:

Designate 2 or more memory channels as select mem-

ory channels. To designate the channel as a select memory channel, choose a memory channel, then push [F3 SEL] in the scan screen, or push [F5 SEL]

in the memory name screen. Scan resume ON/OFF You can select the scan to resume or cancel when de-

tecting a signal, in set mode. Scan resume ON/OFF must be set before operating a scan. See p. 70 for ON/OFF setting and scan resume condition details. 69 Scan speed Scan speed can be selected from 2 levels, high or low, in set mode. See p. 70 for details. Squelch condition SCAN STARTS WITH SQUELCH OPEN SQUELCH CLOSED PROGRAMMED SCAN MEMORY SCAN The scan continues until it is stopped manually, and does not pause even if it detects signals. Scan stops when detecting a signal. Scan pauses on each channel when the scan resume is ON; not applicable when OFF. If you set scan resume ON in scan set mode, the scan pauses for 10 sec. when detecting a signal, then resumes. When a signal disappears while scan is paused, scan resumes 2 sec. later. I Voice squelch control function This function is useful when you dont want unmodu-

lated signals pausing or cancelling a scan. When the voice squelch control function is activated, the receiver checks received signals for voice components. If a receiver signal includes voice components, and the tone of the voice components changes within 1 sec., scan pauses (or stops). If the received signal includes no voice components or the tone of the voice compo-

nents does not change within 1 sec., scan resumes. While M2 is selected with [MENU], push [F5 VSC]

to switch the VSC (Voice Squelch Control) function ON and OFF. VSC appears when the function is activated. The VSC function activates for any scan. The VSC function resumes the scan on unmodu-

lated signals, regardless of the scan resume condi-

tion is set to ON or OFF. I Scan set mode When the squelch is open, scan continues until it is stopped manually it does not pause on detected sig-

nals. When squelch is closed, scan stops when de-

tecting a signal, then resumes according to the scan resume condition. Scan speed and the scan resume condition can be set using the scan set mode. q Push[MENU] to select M2. w Push [F1 SCN] to select scan menu. e Push [F5 SET] to select scan set mode. r Push [F1 ] or [F2 ] to select SCAN Speed item. SCANS 7 VSC indicator S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F5] to turn the VSC function ON and OFF. S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 t Rotate the tuning dial to select scan speed from Push [F1]

high and low. HIGH : scan is faster

: scan is slower LOW y Push [F2 ] to select SCAN Resume item. u Rotate the tuning dial to select scan resume func-

tion from ON and OFF. ON

: when detecting a signal, scan pauses for 10 sec., then resumes. When a signal disap-

pears, scan resumes 2 sec. later.

: when detecting a signal, cancels scanning. OFF i Push [MENU] to return to scan menu. F : 1 O k P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F5]

S C A N S p e e d 1 H I G H F 1 F 2 F 3 F 4 F 5 Push [F1] or [F2]

S C A N R e s u m e 2 O N F 1 F 2 F 3 F 4 F 5 70 8 SCANS I Programmed scan/Fine programmed scan (VFO mode) Programmed scan searches for signals between scan edge memory channels P1 and P2. The default fre-

quencies for these memories are 0.500000 MHz and 29.99999 MHz, respectively. See p. 66 for scan edges programming.

[TS]

[V/M]

q Push [V/M] to select VFO mode, if necessary. w Select the desired operating mode. The operating mode can also be changed while scan-

ning. e Push [TS] to select a tuning step. The tuning step can also be changed while scanning. r Push [MENU] to select M2. t Push [F1 SCN] to select the scan menu. See p. 69 for scan condition. If the [RF/SQL] control function is set as AUTO, the squelch is always open in SSB, CW and RTTY modes. y Push [F1 PRO] to start the programmed scan. The MHz and kHz decimal points blink while scanning. u When the scan detects a signal, the scan stops, pauses or ignores it depending on the resume, VSC setting and the squelch condition. i To cancel the scan, push [F1 PRO]. Rotating the tuning dial during scan also cancels scan operation. If the same frequencies are programmed into the scan edge memory channel P1 and P2, pro-

grammed scan does not start.

[MENU]

Tuning dial Mode keys S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F1]

F : 1 O k P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F1]

P R O G S C A N P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F1] to start/cancel the scanning. DAbout the Fine programmed scan During programmed scan, when a signal is received, scan continues, but the tuning step is temporarily set to 10 Hz. P R O G S C A N P R O F F I N S P N S E T q Follow steps q to y above to start programmed F 1 F 2 F 3 F 4 F 5 scan. w During programmed scan, push [F3 FIN] to switch between programmed scan and fine programmed scan operation. e Push [F1 PRO] to cancel the scan. Rotating the tuning dial during scan also cancels scan operation. Push [F3] to switch between programmed scan and fine pro-

grammed scan. F - P R O G S C A N P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 71 SCANS 8 I Memory scan operation (Memory mode) Memory scan searches through memory channel 1 to 99 for signals. Blank (un-programmed) memory chan-

nels are skipped. q Push [V/M] to select memory mode, if necessary. w Push [MENU] to select M2. e Push [F1 SCN] to select the scan menu. See p. 69 for scan condition. If the [RF/SQL] control function is set as AUTO, the squelch is always open in SSB, CW and RTTY modes. r Push [F1 MEM] to start the memory scan. The MHz and kHz decimal points blink while scanning. At least 2 memory channels must be programmed for memory scan to proceed. t To cancel the scan, push [F1 MEM]. Rotating the tuning dial during scan also cancels scan operation. I Select memory scan Select memory scan searches through memory chan-

nel set as select for signals. See below for setting and deleting select memory channels.

[MENU]

Tuning dial

[V/M]

M E M O S C A N M E M F S E L S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F1] to start/cancel the scanning. M E M O S C A N M E M F S E L S P N S E T q Follow the steps q to r above to start memory F 1 F 2 F 3 F 4 F 5 scan. w During memory scan, push [F3 SEL] to switch be-

tween memory scan and select memory scan. At least 2 memory channels must be set as the select channel. e Push [F1 MEM] to cancel the scan. Rotating the tuning dial during scan also cancels scan operation. Push [F3] to switch between memory scan and select memory scan. S E L - M E M O S C A N M E M F S E L S P N S E T F 1 F 2 F 3 F 4 F 5 DSetting/Cancelling select memory channels All memory channels, except scan edges (P1 and P2), can be set as a select memory channels. Scan menu While the scan menu is selected, push [F3 SEL] to set/cancel the displayed memory channel as a se-

lect channel; or while memory name screen is indi-

cated, push [F5 SEL] to set/cancel the displayed memory channel as a select memory channel. SEL appears when the channel set as a select memory channel. SEL disappears when cancelled. Push [F3 SEL]/[F5 SEL] for 1 sec to cancels all select memory settings. F : 1 O k M E M F S E L S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F3] to set/cancel as a select channel. Memory name screen Select memory inidcator 1 4 . 1 9 5 O O U S B E D T ( ) S E L F 1 F 2 F 3 F 4 F 5 Push [F3] to set/cancel as a select channel. 72 8 SCANS I F scan operation and Fine F scan F scan searches for signals within the specified range with the displayed VFO or memory channel fre-

quency as for center frequency. The frequency range is specied by the span. q Push [V/M] to select VFO mode or memory mode, Keypad

[V/M]

as desired. w Set center frequency of the F scan. e Push [MENU] to select M2. r Push [F1 SCN] to select the scan menu. See p. 69 for scan condition. If the [RF/SQL] control function is set as AUTO, the squelch is always open in SSB, CW and RTTY modes. t Set the F span by pushing [F4 SPN]. 5 kHz, 10 kHz, 20 kHz, 50 kHz, 100 kHz, 500 kHz and 1 MHz are selectable. y Push [F2 F] to start the F scan. Decimal points blink while scanning. u When the scan detects a signal, the scan stops, pauses or ignores it depending on the VSC, resume setting and the squelch condition. y Push [F2 F] to cancel the F scan. Rotating the tuning dial during scan also cancels scan operation. DAbout the Fine F scan During F scan, when a signal is received, scan con-

tinues, but the tuning step is temporarily set to 10 Hz. q Follow steps q to y above to start programmed scan. w During F scan, push [F3 FIN] to switch between F scan and ne F scan operation. e Push [F2 F] to cancel the scan. Rotating the tuning dial during scan also cancels scan operation. 73

[MENU]

Tuning dial S C N M E M S W R T C N V S C F 1 F 2 F 3 F 4 F 5 Push [F1]

F : 1 O k P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F2]

Push [F4] to select the span. F S C A N P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F2] to start/cancel the scanning. F S C A N P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 Push [F3] to switch between programmed scan and fine pro-

grammed scan. F - F S C A N P R O F F I N S P N S E T F 1 F 2 F 3 F 4 F 5 I Tone scan/DTCS code scan operation By monitoring a signal that is being operated with a re-

peater, tone squelch or DTCS, you can determine the tone frequency necessary to open a repeater or the squelch. F 1 q Push [AM/FM] to select FM mode. w Push [MENU] several times to select M1. e Push [F4 TONE] for 1 sec. to enter tone set mode. r Push [F1 TON] to select the tone type to be scanned. Rptr Tone for repeater tone, TSQL Tone for tone squelch and DTCS Code for DTCS code can be selected. When selecting DTCS code to be scanned, push [F5]

several times to select the DTCS code polarity. NN : Normal polarity for both transmit and receive. NR : Normal polarity for transmit and reverse polarity for receive. RN : Reverse polarity for transmit and normal polarity for receive. RR : Reverse polarity for both transmit and receive. t Push [F2 SCN] to start the tone scan function. Rptr Tone SCAN, TSQL Tone SCAN or DTCS Code SCAN blinks when repeater tone scan, tone squelch scan or DTCS code scan is operated, re-

spectively. y When matched tone or code is found, the scan pauses and the tone frequency or code is set for the selected tone as in step r. When the tone scan or DTCS code scan is operated in memory or call channel, the detected tone frequency or code can be used for temporarily. To keep the detected tone frequency or code setting for memory contents, you must over-written the mem-

ory or call channel. u Push [F2 SCN] to cancel the tone scan function. Rotating the tuning dial during scan also cancels scan operation. SCANS 8 A G C D U P C M P T O N S C P F 2 F 3 F 4 F 5 Push [F4] for 1 sec. R p t r T o n e T O N S C N 8 8 . 5 H z F 1 F 2 F 3 F 4 F 5 Push [F1] several times to select tone type. Rpeater tone scan R p t r T o n e S C A N T O N S C N 8 8 . 5 H z F 1 F 2 F 3 F 4 F 5 Push [F2] to start/cancel the scan. Tone squelch tone scan T S Q L T o n e S C A N T O N S C N 8 8 . 5 H z F 1 F 2 F 3 F 4 F 5 Push [F2] to start/cancel the scan. DTCS code scan D T C S C o d e S C A N T O N S C N O 2 3 - N N F 1 F 2 F 3 F 4 F 5 Push [F2] to start/cancel the scan. Push [F1] several times to select porality. 74 9 ANTENNA TUNER OPERATION I Antenna connection and selection The IC-746PRO has 2 antenna connectors for the HF/50 MHz bands, [ANT1] and [ANT2], and 1 antenna connector for the 144 MHz band; a total of 3 antenna connectors. For each operating band the IC-746PRO covers, there is a band memory which can memorize a selected an-

tenna. When you change the operating frequency be-

yond a band, the previously used antenna is automat-

ically selected (see below) for the new band. This function is convenient when you use 2 antennas for HF and 50 MHz bands operation.

[ANT]

144 MHz 21/28/50 MHz 3.5/7 MHz

[ANT2]

[ANT1]

144 MHz band 50 MHz band HF bands AH-4

[ANT2]

[ANT1]

Antenna select function: Auto Once an antenna has been selected for use with a band by pushing [ANT], the antenna is automatically selected whenever that band is accessed.

[EXAMPLE]: a 3.5/7 MHz antenna is connected to

[ANT1], a 21/28/50 MHz antenna is connected to

[ANT2]. When the antenna selector function is set to Auto, an antenna is automatically selected when changing bands. Antenna select function: Manual When Manual is selected, you can use the [ANT1]

and [ANT2], however, band memory does not func-

tion. In this case you must select an antenna manu-

ally. However, the 144 MHz antenna will still be selected automatically.

[EXAMPLE]: an optional antenna tuner and HF an-

tenna are connected to [ANT1] and a 50 MHz an-

tenna is connected to [ANT2]. Antenna select function: OFF In this case, only [ANT1] and the 144 MHz antenna connector can be used. [ANT] switch does not func-

tion. 75 I Antenna tuner operation The internal automatic antenna tuner matches the transceiver to the connected antenna automatically. Once the tuner matches an antenna, the variable ca-

pacitor angles are memorized as a preset point for each frequency range (100 kHz steps). Therefore, when you change the frequency range, the variable capacitors are automatically preset to the memorized point. CAUTION: NEVER transmit with the tuner ON when no antenna is connected. This will damage the transceiver. Be careful of the antenna selection. DTUNER OPERATION Push [TUNER] to turn the internal antenna tuner ON. The antenna is tuned automatically when the antenna SWR is higher than 1.5:1. When the tuner is ON, the TUNE indicator appears. MANUAL TUNING During SSB operation at low voice levels, the internal tuner may not be tuned correctly. In such cases, man-

ual tuning is helpful. Push [TUNER] for 1 sec., to start manual tuning. A side tone is emitted and [TUNER] blinks while tuning. If the tuner cannot reduce the SWR to less than 1.5:1 after 20 sec. of tuning, the [TUNER] switch indicator goes out. AUTOMATIC TUNER START (HF bands only) If you want to deactivate the tuner under conditions of VSWR 1.5:1 or less, use the auto tuner start func-

tion and turn the tuner OFF. This function activates the tuner automatically when the SWR exceeds 1.5:1. This function is turned ON in set mode. (p. 83). PTT TUNER START The tuner is always tuned when the PTT is pushed after the frequency is changed (more than 1% from last-tuned frequency). This function removes the push and hold [TUNER] operation and activates for the rst transmission on a new frequency. This function is turned ON in set mode. (p. 83). Antenna tuner of the IC-PW1 When using an external antenna tuner such as the IC-PW1s tuner, tune with the external antenna tuner, while the internal tuner is turned OFF. After tuning is completed, turn the internal tuner ON. Otherwise, both tuners tune simultaneously and correct tuning may not be obtained. See the instruction manual included with each an-

tenna tuner for their respective operations. ANTENNA TUNER OPERATION 9

[TUNER]

NOTES:

The internal antenna tuner can only tune the HF and 50 MHz bands the 144 MHz band cannot be tuned. DO NOT transmit if no antenna is connected to [ANT1]

and [ANT2]. When 2 antennas are connected, select the antenna to be used with [ANT]. If the SWR is higher than about 1.5:1 when tuning above 100 kHz on an antennas preset point, push [TUNER] for 1 sec. to start manual tuning. The internal tuner may not be able to tune in AM mode. In such cases, push [TUNER] for 1 sec. to manually tune. DIf the tuner cannot tune the antenna Check the following and try again:

the [ANT] connector selection. the antenna connection and feedline. the unaltered antenna SWR. (Less than 3:1 for HF bands;

Less than 2.5:1 for 50 MHz band) the transmit power. (8 W for HF bands; 15 W for 50 MHz band) the power source voltage/capacity. If the tuner cannot reduce the SWR to less than 1.5:1 after checking the above, perform the following:

repeat manual tuning several times. tune with a 50 dummy load and re-tune the antenna. turn power OFF and ON. adjust the antenna cable length.

(This is effective for higher frequencies in some cases.) Some antennas, especially for low bands, have a nar-

row bandwidth. These antennas may not be tuned at the edge of their bandwidth, therefore, tune such an an-

tenna as follows:

[Example]: Suppose you have an antenna which has an SWR of 1.5:1 at 3.55 MHz and an SWR of 3:1 at 3.8 MHz. q Push [TUNER] to turn the antenna tuner ON. w Select CW mode. e Turn OFF the break-in function. (p. 56) r Push [TRANSMIT] to set to the transmit condition. t Set 3.55 MHz and key down. y Set 3.80 MHz and key down. u Push [TRANSMIT] to return to the receive condition. 76 9 ANTENNA TUNER OPERATION I Optional external tuner operation DAH-4 HF/50 MHz AUTOMATIC ANTENNA TUNER The AH-4 matches the IC-746PRO to a long wire an-

tenna more than 7 m/23 ft long (3.5 MHz and above). See the AH-4 instruction manual for AH-4 installation and antenna connection details. AH-4 setting example:

For mobile operation Optional AH-2b antenna element NEVER operate the AH-4 without an antenna wire. The tuner and transceiver will be damaged. NEVER operate the AH-4 when it is not grounded. Transmitting before tuning may damage the trans-

ceiver. Note that the AH-4 cannot tune when using a 12 long wire or multiple of the operating frequency. When connecting the AH-4, the antenna connector assignments are [ANT2] for the internal tuner and

[ANT1] for the AH-4. The antenna indicator in the LCD displays EXT when the AH-4 is connected and selected. DAH-4 operation Tuning is required for each frequency. Be sure to re-tune the antenna before transmitting when you change the frequency even slightly. q Set the desired frequency in an HF or 50 MHz band. The AH-4 may not operate on frequencies outside of ham bands. w Push [TUNER] for 1 sec. TUNER blinks while tuning. e TUNE appears constantly when tuning is com-

plete. When the connected wire cannot be tuned, the TUNE indicator goes out, and the AH-4 is bypassed. At that point the antenna wire connection root is to the trans-

ceiver directly, and not via AH-4 antenna tuner. r To bypass the AH-4 manually, push [TUNER]. For outdoor operation Long wire R WARNING: HIGH VOLTAGE!

NEVER touch the antenna element while tuning or transmitting.

[TUNER]

Connecting the AH-4 Coaxial cable (from AH-4) Transceiver ANT1 Long wire or optional AH-2b Control cable Ground AH-4 77 DATA COMMUNICATION 10 Connect to serial port, parallel port, speaker jack, microphone jack and line IN/OUT jack, etc. See the instruction manual of the application for details. PC TNC RS-232C

*When connecting the squelch line, cpnsult the necessary manual (TNC, etc.) Connect to serial port, parallel port, speaker jack, microphone jack and line IN/OUT jack, etc. See the instruction manual of the application for details. PC TNC or scan converter RS-232C I Connections I When connecting to [DATA]

When using a PC application q DATA IN w GND r DATA OUT (9600 bps) y P SQL*

t AF OUT (1200 bps) e PTT P When using a TNC q DATA IN w GND r DATA OUT (9600 bps) y P SQL*

t AF OUT (1200 bps) e PTT P TX AUDIO GND RX AUDIO SQL PTT TX AUDIO GND RX AUDIO SQL PTT I When connecting to [ACC(1)]

When using a PC application RTTY GND AF SEND 2 8 5 7 3 1 4 6 RTTY OUTPUT GND AUDIO INPUT PTT When using a TNC RTTY GND AF SEND 2 8 5 7 3 1 4 6 Rear panel view RTTY OUTPUT GND AUDIO INPUT PTT I When connecting to [MIC]

When using a PC application MIC INPUT AF OUTPUT MIC GND GND PTT*

AUDIO OUTPUT AF INPUT GND PTT*

Connect to serial port, parallel port, speaker jack, microphone jack and line IN/OUT jack, etc. See the instruction manual of the application for details. PC When using a TNC MIC INPUT AF OUTPUT MIC GND GND PTT*

SQL AFSK OUTPUT AF INPUT GND PTT*

SQL INPUT TNC or scan converter RS-232C

*When using the VOX function, not need to connect. Refer to the external equipment (TNC, etc.). When connecting the squelch line, consult the necessary manual (TNC, etc.). 78

[TRANSMIT]

[TX] indicator Band keys

[MIC GAIN]

[SSB]

[AM/FM] Tuning dial Selected mode indicator appear 10 DATA COMMUNICATION I Packet (AFSK) operation Before operating packet (AFSK) be sure to consult the operating manual that came with your TNC. q Connect a TNC and PC. (p. 77) w Push a band key to select an operating band. e Push [SSB] or [AM/FM] to select the desired operat-

ing mode. After LSB or USB is selected, push [SSB] for 1 sec. to select LSB data or USB data mode, or after AM or FM is selected, push [AM/FM] for 1 sec. to select AM data or FM data mode. Generally, LSB is used on HF bands and FM is used for packet operation on the VHF band. r Rotate the tuning dial to tune the desired signal. t Transmit your AFSK signals using your computers keyboard. Rotate [RF PWR] to set the output power. Relative strength of the transmitted signal is indicated in the Po meter while operating the TNC. When operating in SSB (data) mode, adjust output power so that the ALC reading in the ALC meter stays in the ALC zone. NOTE: When connecting a TNC to the ACC socket on the rear panel, select SSB (LSB/USB) data mode or disconnect the microphone and rotate [MIC GAIN] fully counterclockwise. When SSB data mode is selected, the audio input from the [MIC] connector is automatically cut, and use the audio input from the [ACC(1)]. And, when the SSB data mode is selected, signals are transmitted with the xed conditions as follow;

Speech compressor

: OFF Transmit bandwidth : MID Tx tone (Bass) Tx tone (Trebles)

: 0

: 0 DFrequency indication during AFSK operation When operating AFSK in SSB mode, the indicated fre-

quency is the signals carrier point. Example LSB/LSB data mode Mark freq.: 2125 Hz Shift freq.: 200 Hz 2325 Hz 200 Hz 2125 Hz Carrier point

(Displayed frequency) 79 I Adjusting the TNC output level When setting data transmission speed to 9600 bps, the data signal coming from the TNC is applied exclu-

sively to the internal limiter circuitry to automatically maintain band width. NEVER apply data levels from the TNC of over 0.6 V p-p, otherwise the transceiver will not be able to main-

tain the band width and may possibly interfere with other station. DUsing with a level meter or synchroscope When using a level meter or synchroscope, adjust the TX audio output level (DATA IN level) from the TNC as follows. 0.4 V p-p (0.2 Vrms) 0.20.5 V p-p (0.10.25 Vrms) : acceptable level

: recommended level DNot using a measuring device q Connect transceiver to a TNC. (p. 00) w Enter a test mode (CAL, etc.) on the TNC, then transmit some test data. e When the transceiver fails to transmit the test data or transmits sporadically (TX indicator doesnt lights or ashes):

- Decrease the TNC output level until the transmit indicator lights continuously. When transmission is not successful even though the TX indicator lights continuously:

- Increase the TNC output level. I Data transmission speed For data communication, the transceiver can be set to one of two data speeds: 9600 bps or less speed. q Push [MENU] for 1 sec. to enter set mode. w Push [F1 ] or [F2 ] to select the 9600bps Mode item. e Rotate the tuning dial to turn ON and OFF the 9600 bps mode. ON : 9600 bps of data speed OFF : less than 9600 bps of data speed (default) r Push [MENU] to return to previous indication. DATA COMMUNICATION 10 9 6 O O b p s M o d e 2 1 O F F Select with the tuning dial 9 6 O O b p s M o d e 2 1 O N 80 11 SET MODE I General set mode D Entering set mode Set mode is used for programming infrequently changed values or conditions of functions. Set mode operation q Push [MENU] several times to function menu indi-

cation, if necessary. w Push [MENU] for 1 sec. to enter the set mode. e Push [F1 ] or [F2 ] to select the desired item. r Set the desired condition using the tuning dial. Push [F3] for 1 sec. to select a default condition or value. u Push [MENU] to exit the set mode. D Set mode items 1. LCD Contrast This item adjusts the contrast of the LCD from 0% to 100% in 1% steps.

(default: 50%) 2. LCD Backlight This item adjusts the brightness of the LCD from 0%

to 100% in 1% steps.

(default: 50%) 3. Beep Level This item adjusts the volume level for confirmation beep tones from 0% to 100% in 1% steps. When beep tones, the item 6. Beep (p. 81), are turned OFF, this setting has no effect.

(default: 50%) 4. Beep Level-lmt This item allows you to set a maximum volume level for conrmation beep tones. Conrmation beep tones are linked to the [AF] control until a specied volume level is reached further rotation of the [AF] control will not increase the volume of the beep tones. ON OFF Conrmation beep ON (default) Conrmation beep OFF 5. CAL. Marker This item is used for a simple frequency check of the transceiver. ON OFF Calibration marker ON Calibration marker OFF (default) See p. 93 for calibration procedure. 81

[F1 ]

[F2 ]

[MENU]

Tuning dial L C D C o n t r a s t 1 5 O %

L C D B a c k l i g h t 2 5 O %

B e e p L e v e l 3 5 O %

B e e p L e v e l - l m t 4 O N C a l . M a r k e r 5 O F F Turn the calibration marker OFF after checking the frequency of the transceiver. I General set mode (continued) 6. Beep A beep sounds each time a switch is pushed to con-

rm it. This function can be turned OFF for silent op-

eration. ON OFF Conrmation beep ON (default) Conrmation beep OFF The volume level can be set in 3. Beep Level.

(p. 80) 7. Band Edge Beep A beep sounds when an operating frequency enters or exits an amateur band. This functions independent of the conrmation beep setting (above). ON OFF Band edge beep ON (default) Band edge beep OFF The volume level can be set in 3. Beep Level.

(p. 80) 8. RF/SQL Control The [RF/SQL] control can be set as the RF/squelch control (default), the squelch control only (RF gain is xed at maximum) or Auto (RF gain control in SSB, CW and RTTY; squelch control in AM and FM). SET MODE 11 B e e p 6 O N B a n d E d g e B e e p 7 O N R F / S Q L C o n t r o l 8 R F + S Q L RF+SQL [RF/SQL] control as RF/squelch con-

SQL AUTO trol (default)

[RF/SQL] control as squelch control

[RF/SQL] control as RF gain control in SSB, CW and RTTY; squelch con-

trol in AM and FM 9. Meter Peak Hold This item turns the meter peak hold function ON and OFF. When set to ON (default), peak meter reading are displayed for about 0.5 sec. 10. COMP Meter This item turns the COMP meter indication ON and OFF during transmit. When set to ON, the COMP meter is displayed instead of the SWR meter.

(default: OFF) M e t e r P e a k H o l d 9 O N C O M P M e t e r 1 O O F F 82 11 SET MODE I General set mode (continued) 11. Quick SPLIT When this item is set to ON, pushing [SPLIT] for 1 sec. sets transmit frequency using the displayed fre-

quency and the split offset, set in SPLIT Offset item below, and activate split function automatically. ON OFF Quick split ON (default) Quick split OFF 12. SPLIT Offset This item sets the offset (difference between transmit and receive frequencies) for the quick split function. The offset frequency can be set from 9.999 MHz to

+9.999 MHz in 1 kHz steps. 13. SPLIT LOCK When this item is ON, the tuning dial can be used to adjust the transmit frequency while pushing [XFC]

even while the dial lock function is activated. ON OFF Split lock function ON Split lock function OFF (default) 14. DUP Offset HF This item sets the offset (difference between transmit and receive frequencies) for the duplex operation. However, this setting is used to input the repeater off-

set for an HF band only. The offset frequency can be set from 0.000 MHz to 9.999 MHz in 1 kHz steps. 15. DUP Offset 50M This item sets the offset (difference between transmit and receive frequencies) for the duplex operation. However, this setting is used to input the repeater off-

set for a 50 MHz band only. The offset frequency can be set from 0.000 MHz to 9.999 MHz in 1 kHz steps. 16. DUP Offset 144M This item sets the offset (difference between transmit and receive frequencies) for the duplex operation. However, this setting is used to input the repeater off-

set for a 144 MHz band only. The offset frequency can be set from 0.000 MHz to 9.999 MHz in 1 kHz steps. 83 Q u i c k S P L I T 1 1 O N S P L I T O f f s e t 1 2 O . O O O M H z S P L I T L O C K 1 3 O F F D U P O f f s e t H F 1 4 O . 1 O O M H z D U P O f f s e t 5 O M O . 5 O O M H z 1 5 D U P O f f s e t 1 4 4 M O . 6 O O M H z 1 6 SET MODE 11 17. One Touch Rptr This item turns the one touch repeater function to ON

(DUP- or DUP+) and OFF. When [F2 DUP] is pushed for 1 sec. during M1, the selected offset direction and the programmed duplex offset frequency (depending on the operating fre-

quency band) is set with the displayed frequency. O n e T o u c h R p t r D U P -

1 7 84 11 SET MODE I General set mode (continued) 22. [ANT] Switch You can set the antenna connector selection to auto-

matic, manual or non-selection (when using 1 an-

tenna only for the HF/50 MHz bands). Auto

: The antenna switch is activated and the band memory memorizes the se-

lected antenna. (default) Manual: The antenna switch is activated and OFF selects an antenna manually.

: The antenna switch is not activated and does not function. The [ANT1] con-

nector is always selected in this case. 23. SPEECH Language When the optional UT-102 VOICE SYNTHESIZER UNIT is installed, you can select between English and Japan-

ese as the language. English Japanese : Announces in Japanese

: Announces in English (default) See p. 89 for unit installation. 24. SPEECH Speed When the optional UT-102 VOICE SYNTHESIZER UNIT is installed, you can select between faster or slower synthesizer output. HIGH : Announces faster (default) LOW

: Announces slower See p. 89 for unit installation. 25. SPEECH S-Level When the optional UT-102 VOICE SYNTHESIZER UNIT is installed, you can have frequency, mode and signal level announcement. Signal level announcement can be deactivated if desired. ON OFF

: Announces operating frequency, mode and receiving signal level. (default)

: Announces operating frequency and mode only. See p. 89 for unit installation. 26. Memory Pad Ch This item sets the number of memo pad channels available. 5 or 10 memo pads can be set. 5 : 5 memo pads (default) 10: 10 memo pads 85

[ A N T ] S w i t c h 2 2 A u t o S P E E C H L a n g u a g e 2 3 E n g l i s h S P E E C H S p e e d 2 4 H I G H S P E E C H S - L e v e l 2 5 O N M e m o r y P a d C h 5 2 6 I General set mode (continued) 27. DIAL Auto TS This item sets the auto tuning step function. When ro-

tating the tuning dial rapidly, the tuning step automat-

ically changes several times as selected. There are 2 type of auto tuning steps: HIGH (Fastest) and LOW (Faster). HIGH LOW OFF

: Auto tuning step is turned ON. Approx. 5 times fastest tuning step during rapid rotation (default)

: Auto tuning step is turned ON. Approx. 2 times faster tuning step dur-

ing rapid rotation

: Auto tuning step is turned OFF. 28. MIC U/D Speed This item sets the rate at which frequencies are scanned when the microphone [UP]/[DN] switches are pushed and held. High or low can be selected. HIGH LOW

: High speed (default, 50 tuning steps/sec.)

: Low speed (25 tuning steps/sec.) 29. Quick RIT Clear This item selects the RIT/TX frequency clearing in-

struction with [PBTC]. ON OFF

: Clears the RIT/TX frequency when

[PBTC] is pushed momentarily.

: Clears the RIT/TX frequency when

[PBTC] is pushed for 1 sec. (default) 30. BW Popup (PBT) This item turns the PBT shifting value indication ON and OFF during [TWIN PBT] control operation. When set to ON, the shifting value is displayed above the multi-function switches.

(default: ON) 31. BW Popup (FIL) This item turns the IF filter width indication ON and OFF when selecting with [FILTER]. When set to ON, the filter width is displayed above the multi function switches.

(default: ON) SET MODE 11 D I A L A u t o T S 2 7 H I G H M I C U / D S p e e d 2 8 H I G H Q u i c k R I T C l e a r 2 9 O F F B W P o p u p ( P B T ) 3 O O N B W P o p u p ( F I L ) 3 1 O N 86 11 SET MODE I General set mode (continued) 32. SSB/CW Synchronous Tuning This item selects the displayed frequency shift func-

tion from ON and OFF. When this function is activated, the receiving signal can be kept to receive even when the operating mode is changed between SSB and CW. ON OFF

: The displayed frequency shifts when the operating mode is changed be-

tween SSB and CW.

: The displayed frequency does not shift.

(default) The frequency shifting value may differ according to the CW pitch setting. 33. CW Normal Side Selects the carrier point of CW mode from LSB and USB. LSB USB

: The carrier point is set to LSB side.

(default)

: The carrier point is set to USB side. 34. KEYER 1st Menu This item selects the appearing menu when [F4 KEY]

is pushed in M1 at first, from KEYER-Root and KEYER-SEND. KEYER-Root KEYER-SEND

: Selects memory keyer menu at rst (default)

: Selects keyer SEND menu at rst 35. External Keypad This item sets the external keypad capability. OFF

: External keypad does not func-

tion. (default) KEYER SEND : Pushing one of external keypad switches, transmits the desired keyer memory contents during CW mode operation. For your information The diagram as at right shows the equivalent circuit of an external keypad and connects to the pin 3 and pin 7 of the [MIC] connector (p. 12) 87 S S B / C W S y n c T u n 3 2 O F F C W N o r m a l S i d e L S B 3 3 K E Y E R 1 s t M e n u 3 4 K E Y E R - R o o t E x t e r n a l K e y p a d 3 5 O F F 4.7k 5%

2.2k 5%

1.5k 5%

1.5k 5%

To [MIC] connector pin e S4

(T4/M4) S3

(T3/M3) S2

(T2/M2) S1

(T1/M1) To [MIC] connector pin u USER EXTERNAL KEYPAD I General set mode (continued) 36. CI-V Baud Rate This item sets the data transfer rate. 300, 1200, 4800, 9600, 19200 bps and Auto are available.

: Auto baud rate (default) Auto

: 300 bps 3OO

: 1200 bps 12OO

: 4800 bps 48OO

: 9600 bps 96OO 192OO : 19200 bps When Auto is selected, the baud rate is automati-

cally set according to the connected controller or re-

mote controller. 37. CI-V Address To distinguish equipment, each CI-V transceiver has its own Icom standard address in hexadecimal code. The IC-746PROs address is 66h. When 2 or more IC-746PROs are connected to an optional CT-17 CI-V LEVEL CONVERTER, rotate the tun-

ing dial to select a different address for each IC-

746PRO in the range 01h to 7Fh. 38. CI-V Transceive Transceive operation is possible with the IC-746PRO connected to other Icom HF transceivers or receivers. ON OFF

: Transceive ON (default)

: Transceive OFF When ON is selected, changing the frequency, op-

erating mode, etc. on the IC-746PRO automatically changes those of connected transceivers (or re-

ceivers) and vice versa. 39. CI-V 731 Mode When connecting the IC-746PRO to the IC-735 for transceive operation, you must change the operating frequency data length to 4 bytes. This item must be set to ON only when operating the transceiver with the IC-735. ON OFF

: 4 bytes of frequency data

: 5 bytes of frequency data (default) SET MODE 11 C I - V B a u d R a t e A u t o 3 6 C I - V A d d r e s s 3 7 6 6 h C I - V T r a n s c e i v e 3 8 O N C I - V 7 3 1 M o d e 3 9 O F F 88 11 SET MODE I Tone control set mode DEntering tone control set mode Tone levels (bass and treble) for each transmit and re-

ceive audio can be set for each phone mode indepen-

dently. Set mode operation q Push [MENU] several times to select M2. w Push [F4 TCN] to select the tone control set mode. e Push [F1 ] or [F2 ] to select the desired item. r Push [SSB] or [AM/FM] to select the desired oper-

ating mode. t Set the desired condition using the tuning dial. Push [F3] for 1 sec. to select a default value. y Push [MENU] to exit the set mode. DTone control set mode items

[F1 ]

[F2 ] [F4 TCN]

[MENU]

Tuning dial 1. TX Bass This item adjusts the bass level of the transmit audio tone from 5 dB to +5 dB in 1 dB steps. T X B a s s S S B 1 O 2. TX Treble This item adjusts the treble level of the transmit audio tone from 5 dB to +5 dB in 1 dB steps. T X T r e b l e S S B 2 O 3. RX Bass This item adjusts the bass level of the receive audio tone from 5 dB to +5 dB in 1 dB steps. R X B a s s S S B 3 O 4. RX Treble This item adjusts the treble level of the receive audio tone from 5 dB to +5 dB in 1 dB steps. R X T r e b l e S S B 4 O 89 OPTION INSTALLATION 12 I Opening the transceivers case Follow the case and cover opening procedures shown here when you want to install an optional unit or adjust the internal units, etc. CAUTION: DISCONNECT the DC power cable from the transceiver before performing any work on the transceiver. Otherwise, there is danger of elec-

tric shock and/or equipment damage. q Remove 2 screws from the left side of the trans-

ceiver to remove the carrying handle as shown at right. w Remove 6 screws from the top of the transceiver and 6 screws from the sides, then lift up the top cover. e Turn the transceiver upside down. r Remove 6 screws from the bottom of the trans-

ceiver, then lift up the bottom cover. I UT-102 VOICE SYNTHESIZER UNIT The UT-102 announces the accessed readouts fre-

quency, mode, etc. (S-meter level can also be an-

nounced p. 84) in a clear, electronically-generated voice, in English (or Japanese). Push [LOCK/SPCH] for 1 sec. to announce the fre-

quency, etc. q Remove the top and bottom covers as shown above. w Remove the protective paper attached to the bot-

tom of the UT-102 to expose the adhesive strip. e Plug UT-102 into J1920 on the MAIN unit as shown in the diagram at right. r Adjust the trimmer, SPCH LVL: R1925 on the MAIN unit, to set the speech level if desired. Refer the il-

lustration at right. t Return the top and bottom covers to their original positions. MAIN unit UT-102 R1925 J1920 90 12 OPTION INSTALLATION I CR-338 HIGH STABILITY CRYSTAL UNIT By installing the CR-338, the total frequency stability of the transceiver will be improved. q Remove the bottom covers as shown in the previ-

ous page. w Remove 4 screws from the shield cover of the RF unit, then lift up the shield cover. There is an earth spring with the shield cover, so be careful for lost it when removing the cover. Earth spring Shield cover TUNER

(antenna tuner) connector RF unit e Remove 8 screws from the RF unit, disconnect J1, Black belt J121 and J151, then remove the RF unit. r Remove the supplied internal crystal and replace with the CR-338. t Return the RF unit, J1, J121 and J151 to their orig-

inal positions. Blue belt J151 Blue J1 Black J121 Red CR-338 Supplied crystal Red belt Soldering points RF unit Connect a frequency counter, then adjust the ferquency to be 64.00000 MHz. RF unit J262 2LO IN L1901 y Connect a frequency counter to the J262, 2LO IN, to be then adjust 64.00000 MHz with the L1901 on the RF unit. the reference frequency u Return the J262, shield cover, earth spring and bot-

tom covers to their original positions. 91 MAINTENANCE 13 I Troubleshooting The following chart is designed to help you correct problems which are not equipment malfunctions. If you are unable to locate the cause of a problem or solve it through the use of this chart, contact your near-

est Icom Dealer or Service Center. PROBLEM POSSIBLE CAUSE SOLUTION Power does not come on when the [POWER] switch is pushed. Power cable is improperly connected. Fuse is blown. Re-connect the DC power cable correctly. Check for the cause, then replace the fuse with the spare one.

(Fuses are installed in the DC power cable and the internal PA unit.) REF. p. 16 p. 92 No sounds come out from the speaker. Volume level is too low. Rotate [AF] clockwise to obtain a suitable lis-

p. 23 The squelch is closed. Turn [RF/SQL] to 10 oclock position to open the p. 24 tening level. Sensitivity is too low, and only strong signals are au-

dible. The transceiver is in transmitting condition. Push [TRANSMIT] to receive or check the p. 25 SEND line of an external unit, if desired. The antenna is not connected properly. The antenna for another band is selected. Re-connect to the antenna connector. Select an antenna suitable for the operating fre-

p. 75 squelch. quency. The antenna is not properly tuned. Push [TUNER] for 1 sec. to manually tune the antenna. pgs. 76, 77 The attenuator is activated. Push [P.AMP/ATT] for 1 sec. to select ATT OFF. p. 48 Received audio is unclear or distorted. Wrong operating mode is selected. PBT function is activated. Noise blanker is turned ON when receiving a Select a suitable operating mode. Push [PBTC] for 1 sec. to reset the function Push [NB] to turn the noise blanker OFF. p. 23 p. 52 p. 51 strong signal. Preamp is activated. The noise reduction is activated and the [NR]

control is too far clockwise. The antenna switch has not been activated. Push [P.AMP/ATT] once or twice to turn the function OFF. Set the [NR] control for maximum readability. p. 48 p. 53 Set the antenna switch in set mode to Auto or Manual. p. 84 The operating frequency is not set to a ham band. Set the frequency to a ham band. The [ANT] switch does not function Transmitting is impossible. Output power is too low.

[RF PWR] is set too far counterclockwise

[MIC GAIN] is set too far counterclockwise The antenna for another band is selected. The antenna is not properly tuned. Rotate [RF PWR] clockwise. Set [MIC GAIN] to a suitable position. Select an antenna suitable for the operating fre-

quency. Push [TUNER] for 1 sec. to manually tune the antenna. Push [RIT] or [TX] to turn the function OFF. No contact possible with another station. RIT or TX function is activated. Transmit signal is unclear or distorted. Repeater cannot be ac-

cessed. Split frequency and/or duplex function are acti-

vated. Push [SPLIT] and/or [F2 DUP] (in M1) to turn the function OFF.

[MIC GAIN] is set too far clockwise Set [MIC GAIN] to a suitable position. Split frequency or duplex function is not acti-

vated. Push [SPLIT] and/or [F2 DUP] (in M1) to turn the function ON Programmed subaudible tone frequency is Reset the frequency using set mode. wrong. p. 19 p. 25 p. 25 p. 75 pgs. 76, 77 pgs. 48, 56 pgs. 58, 44 p. 25 pgs. 44, 58 p. 45 Programmed scan does not stop. Squelch is open.

[RF/SQL] is assigned to RF gain control and squelch is open. Set [RF/SQL] to the threshold point. Reset [RF/SQL] control assignment and set it to the threshold point. p. 24 pgs. 24, 81 Programmed scan does not start. The same frequencies have been programmed in scan edge memory channels P1 and P2. Program different frequencies in scan edge memory channel P1 and P2. p. 66 Memory scan does not start 2 or more memory channels have not been programmed. Program more than 2 memory channels. p. 63 Select memory scan does not start 2 or more memory channels have not been designated as select channels. Designate more than 2 memory channels as se-

lect channels for the scan. p. 72 92 R E W O P I E V E C E R I T M S N A R T N A C S 13 MAINTENANCE PROBLEM Y The displayed frequency A does not change properly. L P S D I POSSIBLE CAUSE The dial lock function is activated. A set mode screen is selected. SOLUTION Push [LOCK/SPCH] to turn the function OFF. Push [MENU] several times to exit the set mode. The internal CPU has malfunctioned. Reset the CPU. REF. p. 53 p. 93 CAUTION: DISCONNECT the DC power cable from the transceiver when changing a fuse. 30 A fuse I Fuse replacement If a fuse blows or the transceiver stops functioning, try to nd the source of the problem, and replace the dam-

aged fuse with a new, rated fuse. The IC-746PRO has 2 types of fuses installed for transceiver protection. DC power cable fuses ................................ FGB 30 A Circuitry fuse ................................................ FGB 5 A DDC power cable fuse replacement Refer the figure illustrated at right for the DC power cable fuse replacement. DCircuitry fuse replacement The 13.8 V DC from the DC power cable is applied to all units in the IC-746PRO, except for the power am-

plier, through the circuitry fuse. This fuse is installed in the PA unit. q Remove the top cover as shown on p. 89. w Remove 11 screws from the PA shielding plate, then remove the plate. e Replace the circuitry fuse as shown in the diagram at right. r Replace the PA shielding plate and top cover. Fuse I Tuning dial brake adjustment The tension of the tuning dial may be adjusted to suit your preference. The brake adjustment screw is located on the right side of the tuning dial. See the gure at right. Turn the brake adjustment screw clockwise or counter-

clockwise to obtain a comfortable tension level while turning the dial continuously and evenly in one direction. 93 Light Heavy I Resetting the CPU When rst applying power or when the function seems to be displaying erroneous information, reset the CPU as follow:

q Make sure the transceiver power is OFF. w While pushing [M-CL] and [F-INP], push [POWER]

for 1 sec. to turn power ON. The internal CPU is reset. The transceiver displays its initial VFO frequency when resetting is complete. e Correct the set mode settings after resetting, if de-

sired. NOTE: Resetting CLEARS all programmed con-

tents in memory channels and returns programmed values in set mode to default values. I Frequency calibration (approximate) A very accurate frequency counter is required to cali-

brate the frequency of the transceiver. However, a rough check may be performed by receiving radio sta-

tion WWV, or other standard frequency signals. CAUTION: Your transceiver has been thoroughly adjusted and checked at the factory before being shipped. You should not calibrate frequencies, ex-

cept for special reasons. q Push [SSB] to select USB mode. w Push [PBTC] for 1 sec. to clear the PBT settings and make sure that the RIT/TX function is not ac-

tivated. e Set the frequency to the standard frequency station minus 1 kHz. When receiving WWV (10.000.00 MHz) as a standard frequency, set the operating frequency for 9.999.00 MHz. Other standard frequencies can also be used. r Push [MENU] several times to select M1 or M2, if necessary. t Push [MENU] for 1 sec. to select the set mode screen. y Push [F1 ] or [F2 ] several times to select the CAL. Marker item. u Rotate the tuning dial clockwise to turn the calibra-

tion marker ON. Side tone may be heard. i Adjust [CAL] pot on the rear side of the transceiver for a zero beat with the received standard signal. Zero beat means that two signals are exactly the same frequency, resulting in a single tone being emitted. o Rotate the tuning dial counterclockwise to turn the calibration marker OFF.

!0 Push [MENU] to exit set mode. MAINTENANCE 13

[POWER]

[F-INP] [M-CL]

[MENU]

[SSB]

[PBTC]

[RF/SQL] [AF]

[P.AMP/ATT]

[RIT]

[CLEAR]

Calibration marker item C A L . M a r k e r 5 O N

[CAL]

94 14 CONTROL COMMAND I Remote jack (CI-V) information CI-V connection example The transceiver can be connected through an optional CT-17 CI-V LEVEL CONVERTER to a personal computer equipped with an RS-232C port. The Icom Communi-

cations Interface-V (CI-V) controls the following func-

tions of the transceiver. Up to 4 Icom CI-V transceivers or transceivers can be connected to a personal computer equipped with an RS-232C port. See p. 87 for setting the CI-V condition using set mode. Data format The CI-V system can be operated using the following data formats. Data formats differ according to com-

mand numbers. A data area or sub command is added for some commands. IC-746PRO BC-25

(optional) 915 V DC personal computer ct- 17 mini-plug cable Controller to IC-746PRO OK message to controller q FE FE w 66 e E0 r Cn t Sc y Data area u FD FE FE E0 66 FB FD l e b m a e r P

) d e x i f

(

e d o c i s r e v e c s n a r T s s e r d d a t l u a f e d s r e l l o r t n o C s s e r d d a t l u a f e d r e b m u n d n a m m o C l

) e b a t d n a m m o c e h t e e s

(

r e b m u n d n a m m o c b u S l

) e b a t d n a m m o c e e s

(

r o f a t a d e d o c D C B y r o m e m r o y c n e u q e r f y r t n e r e b m u n e g a s s e m f o d n E

) d e x i f

(

e d o c l e b m a e r P

) d e x i f

(

e d o c s r e l l o r t n o C s s e r d d a t l u a f e d i s r e v e c s n a r T s s e r d d a t l u a f e d

) d e x i f

(

e d o c K O e d o c G N

) d e x i f

(

e g a s s e m f o d n E

) d e x i f

(

e d o c FE FE E0 q w 66 e Cn r Sc t Data area y FD u FE FE E0 66 FA FD IC-746PRO to controller NG message to controller Command table Command Sub command Description Command Sub command Description 00 01 02 03 04 05 06 07 Same as command 06 Send frequency data Send mode data 00 01 02 03 04 05 07 08 00 01 A0 Read band edge frequencies Read operating frequency Read operating mode Set operating frequency Select LSB Select USB Select AM Select CW Select RTTY Select FM Select CW-R Select RTTY-R Select VFO mode Select VFO A Select VFO B Equalize VFO A and VFO B 07 08 09 0A 0B 0C 0D 0E B0 00010101*

0102 00 01 02 03 12 13 22 23 Exchange VFO A and VFO B Select memory mode Select memory channel

*P1=0100, P2=0101 Select the call channel Memory write Memory to VFO Memory clear Read offset frequency Set offset frequency Scan stop Programmed/memory scan start Programmed scan start F scan start Fine programmed scan start Fine F scan start Memory scan start Select memory scan start 95 Command table (continued) Command Sub command Description 0E 0F 10 11 12 13 14 15 16 A1A7 B0 B1 D0 D3 00 01 10 11 12 00 01 02 03 04 05 06 07 08 Set F scan span (A1=5 kHz, A2=10 kHz, A3=20 kHz, A4=50 kHz, A5=100 kHz, A6=500 kHz, A7=1 MHz) Set as non-select channel Set as select channel Set scan resume OFF Set scan resume ON Turn the split function OFF Turn the split function ON Select simplex operation Select DUP operation Select +DUP operation Select 10 Hz (1 Hz) tuning step Select 100 Hz tuning step Select 1 kHz tuning step Select 5 kHz tuning step Select 9 kHz tuning step Select 10 kHz tuning step Select 12.5 kHz tuning step Select 20 kHz tuning step Select 25 kHz tuning step Select/read attenuator (0=OFF, 1=ON) Select/read antenna selection

(0=ANT1, 1=ANT2) Announce with voice synthesizer

(00=all data; 01=frequency and S-meter level; 02=receive mode) 01 + Level data [AF] level setting (0=max. CCW to 00 01 02 255=max. CW) 02 + Level data [RF] level setting (0=max. CCW to 255=11 oclock) 03 + Level data [SQL] level setting (0=11 oclock to 255=max. CW) 06 + Level data [NR] level setting (0=min. to 255=max.) 07 + Level data Inside [TWIN PBT] setting or IF shift setting (0=max. CCW, 128=center, 255=max. CW) 08 + Level data Outside [TWIN PBT] setting

(0=max. CCW, 128=center, 255=max. CW) 09 + Level data [CW PITCH] setting (0=300 Hz, 128=600 Hz, 255=900 Hz) 0A + Level data [RF PWR] setting (0=mini. to 255=max.) 0B + Level data [MIC GAIN] setting (0=mini. to 255=max.) 0C + Level data [KEY SPEED] setting (0=slow to 255=fast) 0D + Level data [NOTCH] setting (0=low freq. to 255=high freq.) 0E + Level data COMP Level Delay setting (0=0 to 10=10) 0F + Level data Break-IN DELAY setting (20=2.0d 01 02 11 12 13 02 to 130=13.0d) Read squelch condition Read S-meter level Read RF power meter Read SWR meter Read ALC meter Preamp (0=OFF; 1=preamp 1;

2=preamp 2) CONTROL COMMAND 14 Command Sub command Description 16 19 1A 12 22 40 41 42 43 44 45 46 47 48 49 4B 4C 00 00 01 02 03 04 0501 0502 0503 0504 0505 0506 0507 0508 0509 0510 0511 0512 0513 0514 0515 0516 AGC selection (0=OFF; 1=Slow;

2=Mid; 3=Fast) Noise blanker (0=OFF; 1=ON) Noise reduction (0=OFF; 1=ON) Auto notch (0=OFF; 1=ON) Repeater tone (0=OFF; 1=ON) Tone squelch (0=OFF; 1=ON) Speech compressor (0=OFF; 1=ON) Monitor (0=OFF; 1=ON) VOX function (0=OFF; 1=ON) Break-in (0=OFF; 1=semi break-

in; 2=full break-in) Manual notch (0=OFF; 1=ON) RTTY lter (0=OFF; 1=ON) DTCS (0=OFF; 1=ON) VSC (0=OFF; 1=ON) Read the transceiver ID Send/read memory contents (see p. 97 for details) Send/read band stacking register contents (see p. 97 for details) Send/read memory keyer con-

tents (see p. 97 for details) Send/read the selected lter width

(0=50 Hz to 40/31=3600/2700 Hz) Send/read the selected AGC time constant (0=OFF, 1=0.1/0.3 sec. to 13=6.0/8.0 sec.) Send/read LCD contrast (0=0% to 255=100%) Send/read LCD backlight (0=0% to 255=100%) Send/read beep gain (0=min. to 255=max.) Send/read beep gain limit (0=OFF, 1=ON) Send/read calibration marker

(0=OFF, 1=ON) Send/read conrmation beep

(0=OFF, 1=ON) Send/read band edge beep

(0=OFF, 1=ON) Send/read RF/SQL control set

(0=Auto, 1=SQL, 2=RF+SQL) Send/read meter peak hold set

(0=OFF, 1=ON) Send/read COMP meter set

(0=OFF, 1=ON) Send/read quick split set (0=OFF, 1=ON) Send/read split offset 9.999 to

+9.999 MHz (see p. 98 for details) Send/read split lock set (0=OFF, 1=ON) Send/read duplex offset 0.000 to 9.999 MHz for HF (see p. 98 for details) Send/read duplex offset 0.000 to 9.999 MHz for 50 MHz band (see p. 98 for details) Send/read duplex offset 0.000 to 9.999 MHz for 144 MHz band

(see p. 98 for details) 96 14 CONTROL COMMAND Command table (continued) Command Sub command Description Command Sub command Description 1A 1A 0517 0518 0519 0520 0521 0522 0523 0524 0525 0526 0527 0528 0529 0530 0531 0532 0533 0534 0535 0536 0537 0538 0539 0540 0541 0542 0543 0544 0545 0546 0547 Send/read one touch repeater set

(0=DUP, 1=DUP+) Send/read auto repeater set

(0=OFF, 1=ON-1, 2=ON-2) Send/read tuner auto start set

(0=OFF, 1=ON) Send/read PTT tune set (0=OFF, 1=ON) Send/read 9600 bps mode set

(0=OFF, 1=ON) Send/read antenna selection

(0=OFF, 1=Manual, 2=Auto) Send/read speech language

(0=English, 1=Japanese) Send/read speech speed (0=Slow, 1=Fast) Send/read S-level speech (0=OFF, 1=ON) Send/read memo pad numbers

(0=5 ch, 1=10 ch) Send/read main dial auto TS

(0=OFF, 1=Low, 2=High) Send/read mic. up/down speed

(0=Low, 1=High) Send/read quick RIT/TX clear function (0=OFF, 1=ON) Send/read PBT shifting value popup set (0=OFF, 1=ON) Send/read IF lter width popup set (0=OFF, 1=ON) Send/read SSB/CW synchronous tuning function (0=OFF, 1=ON) Send/read CW normal side set

(0=LSB, 1=USB) Send/read keyer 1st menu set

(0=Keyer-root, 1=Keyer-send) Send/read external keypad set

(0=OFF, 1=Keyer send) Send/read CI-V transceive set

(0=OFF, 1=ON) Send/read CI-V 731 mode set

(0=OFF, 1=ON) Send/read speech compressor level set (0=0 to 10=10) Send/read SSB TX Tone (Bass) level (0 =5 to 10=+5) Send/read SSB TX Tone (Treble) level (0=5 to 10=+5) Send/read SSB RX Tone (Bass) level (0 =5 to 10=+5) Send/read SSB RX Tone (Treble) level (0=5 to 10=+5) Send/read AM TX Tone (Bass) level (0 =5 to 10=+5) Send/read AM TX Tone (Treble) level (0=5 to 10=+5) Send/read AM RX Tone (Bass) level (0 =5 to 10=+5) Send/read AM RX Tone (Treble) level (0=5 to 10=+5) Send/read FM TX Tone (Bass) level (0 =5 to 10=+5) 0548 0549 0550 0551 0552 0553 0554 0555 0556 0557 0558 0559 0560 0561 0562 0563 0564 0565 0566 0567 0568 0569 0570 0571 0572 0573 0574 0575 0576 Send/read FM TX Tone (Treble) level (0=5 to 10=+5) Send/read FM RX Tone (Bass) level (0 =5 to 10=+5) Send/read FM RX Tone (Treble) level (0=5 to 10=+5) Send/read contact number style

(0=Normal, 1=190ANO, 2=190ANT, 3=90NO, 4=90NT) Send/read count up trigger chan-

nel (1=M1, 2=M2, 3=M3, 4=M4) Send/read present number

(19999) Send/read CW side tone gain

(0=min. to 255=max.) Send/read CW side tone gain limit

(0=OFF, 1=ON) Send/read CW keyer repeat time

(1=1 sec. to 60=60 sec.) Send/read CW keyer dot/dash ratio (28=1:1:2.8 to 45=1:1:4.5) Send/read rise time (0=2 msec., 1=4 msec., 2=6 msec., 3=8 msec.) Send/read paddle polarity

(0=Normal, 1=Reverse) Send/read keyer type (0=Straight, 1=Bug-key, 2=ELEC-Key) Send/read mic. up/down keyer set

(0=OFF, 1=ON) Send/read RTTY lter bandwidth

(0=250 Hz, 1=300 Hz, 2=350 Hz, 3=500 Hz, 4=1 kHz) Send/read twin peak lter (0=OFF, 1=ON) Send/read RTTY mark frequency

(0=1275 Hz, 1=1615 Hz, 2=2125 Hz) Send/read RTTY shift width

(0=170 Hz, 1=200 Hz, 2=425 Hz) Send/read RTTY keying polarity

(0=Normal, 1=Reverse) Send/read RTTY decode USOS

(0=OFF, 1=ON) Send/read RTTY decode new line code (0=CR,LF,CR+LF, 1=CR+LF) Send/read number of RTTY de-

coder line (0=2 lines, 1=3 lines) Send/read scan speed (0=Low, 1=High) Send/read scan resume (0=OFF, 1=ON) Send/read NB level (0=0% to 255=100%) Send/read VOX gain (0=0% to 255=100%) Send/read anti VOX gain (0=0% to 255=100%) Send/read VOX delay (0=0.0 sec. to 20=2.0 sec.) Send/read Break-IN delay set

(20=2.0d to 130=13.0d) 97 Command table (continued) Command Sub command Description 1A 0577 06 07 08 00 01 02 00 01 1B 1C Send/read MONITOR level (0=0%

to 255=100%) Send/read DATA mode (0=OFF, 1=ON) Send/read SSB transmit band-

width (0=WIDE, 1=MID, 2=NAR) Send/read DSP lter shape

(0= sharp, 1= soft) Set/read repeater tone frequency

(see p. 98 for details) Set/read TSQL tone frequency

(see p. 98 for details) Set/read DTCS code and polarity

(see p. 98 for details) Set/read the transceivers condi-

tion (0=Rx; 1=Tx) Set/read antenna tuner condition

(0=OFF, 1=ON, 2=Start tuning or while tuning) D To send/read memory contents When sending or reading memory contents, additional code as follows must be added to appoint the memory channel. Additional code: 00000102 (0100=P1, 0101=P2, 0102=Call) D Band stacking register To send or read the desired band stacking registers con-

tents, combined code of the frequency band and register codes as follows are used. For example, when sending/reading the oldest contents in the 21 MHz band, the code 0703 is used. Frequency band code Code Frequency band Frequency range (unit: MHz) 01 02 03 04 05 06 07 08 09 10 11 12 1.8 3.5 7 10 14 18 21 24 28 50 144 GENE 1.800000 1.999999 3.400000 4.099999 6.900000 7.499999 9.90000010.499999 13.90000014.499999 17.90000018.499999 20.90000021.499999 24.40000025.099999 28.00000029.999999 50.00000054.000000 144.000000148.000000 Other than above Register code Code 01 02 03 Registered number 1 (latest) 2 3 (oldest) CONTROL COMMAND 14 D Codes for memory keyer contents To send or read the desired memory keyer contents, the channel and character codes as follows are used. Channel code Code 01 02 03 04 Channel number M1 M2 M3 M4 Characters code Character ASCII code 09 AZ space

/

?

,

.

^

, 3039 415A 20 2F 3F 2C 2E 5E 2A Description Numerals Alphabetical characters Word space Symbol Symbol Symbol Symbol e.g., to send BT, enter ^4254 Inserts contact number (can be used for 1 channel only) D Codes for memory name contents To send or read the desired memory name settings, the char-

acter codes, instructed codes for memory keyer contents as above, and follows are additionally used. Characters code Alphabetical characters Character ASCII code Character ASCII code az 617A Characters code Symbols Character ASCII code Character ASCII code

!

$

&

?

+

:

=

>

)

]

}

_ 21 24 26 3F 27 2B 3A 3D 3E 29 5D 7D 5F

#

%

`

;

<

(

[

{

|

23 25 5C 22 60 2D 3B 3C 28 5B 7B 7C 7E 98 14 CONTROL COMMAND D Split/Duplex frequency setting The following data sequence is used when sending/reading the split or duplex frequency setting. q w e X 0 X X 0 X r*

XX

) d e x i f

(

0

:

t i g d i z H 0 0 1 9 0

:

t i i g d z H k 0 0 1 9 0

:

t i g d i z H k 1 9 0

:

t i i g d z H k 0 1

) d e x i f

(

0

:

t i i g d z H M 0 1 4 0

:

t i g d i z H M 1 n o n o i t c e r i d

+

=

0 0 i t c e r i d

=

1 0

:

n o i t c e r i D

*Not need to enter for duplex frqeuency setting. D Repeater tone/tone squelch frequency setting The following data sequence is used when sending/reading the DTCS code and polarity setting. q*

w e 0 0 X X X X i 2 0

:

t i g d z H 0 0 1 i 9 0

:

t i g d z H 0 1 9 0

:

t i g d z H 1 i i 9 0

:

t i g d z H 1

. 0 i

*

0

:

t i g d d e x F i i

*

0

:

t i g d d e x F i

*Not necessary when setting a frequency. D DTCS code and polarity setting The following data sequence is used when sending/reading the DTCS code and polarity setting. q w e X X 0 X X X

:

y t i r a o p l t i m s n a r T l

:

y t i r a o p e v e c e R i e s r e v e R

=

1 l a m r o N

=

0 e s r e v e R

=

1 l a m r o N

=

0 0

:

t i i g d d e x F i 7 0

:

t i g d i t s 1 7 0

:

t i i g d d n 2 7 0

:

t i i g d d r 3 99 General Frequency coverage Receive

:

Transmit

(Unit: MHz) Receiver Receive system 0.030 60.000000*

108.000 174.000000*

2.000000 1.800 3.999999 3.500 7.000 7.300000 10.100 10.150000 14.000 14.350000 18.068 18.168000 21.000 21.450000 24.890 24.990000 28.000 29.700000 50.000 54.000000 144.000 148.000000

*Some frequency ranges are not guaranteed. Mode No. of memory ch.

: USB, LSB, CW, RTTY, AM, FM

: 102 (99 regular, 2 scan edges and 1 Antenna connector Usable temp. range Frequency stability call)

: SO-2393 (2 for HF/50 MHz and 1 for 144 MHz; 50 )

: 10C to +60C ; +14F to +140F

: Less than 7 ppm from 1 min. to 60 min. after power ON. After that, rate of stability is less than 1 ppm/hr. at 25C (+77F). Temperature uctuations 0C to

+50C (+20F to +122F) less than 5 ppm. Frequency resolution Power supply Power consumption

: 1 Hz

: 13.8 V DC 15% (negative ground)

:

Transmit Receive Dimensions

(projections not incl.) Weight (approx.) ACC 1 connector ACC 2 connector DATA connector CI-V connector 23.0 A 2.2 A 3.0 A Max. power Standby Max. audio

: 287(W)120(H)316.5(D) mm 13516(W)42332(H)121532(D) in

: 9.0 kg; 19 lb 13 oz

: 8-pin DIN connector

: 7-pin DIN connector

: Mini DIN 6-pin

: 2-conductor 3.5 (d) mm (18) Transmitter Output power (continuously adjustable):

SSB/CW/RTTY/FM Less than 5 to 100 W AM Less than 5 to 40 W Modulation system

:

SSB AM FM Spurious emission Carrier suppression Unwanted sideband suppression TX variable range Mic. connector ELEC-KEY connector KEY connector SEND connector ALC connector Digital PSN modulation Digital low power modulation Digital phase modulation

: 50 dB (HF bands) 60 dB (50/144 MHz)

: 40 dB

: 55dB

: 9.99 kHz

: 8-pin connector (600 )

: 3-conductor 6.35(d) mm (14)

: 3-conductor 6.35(d) mm (14)

: Phono (RCA)

: Phono (RCA) SPECIFICATIONS 15

: Triple conversion superheterodyne system Intermediate frequencies:

1st 2nd 3rd 64.455 MHz 455 kHz 36 kHz Sensitivity (typical) SSB, CW, RTTY

(10 dB S/N)

:

AM (10 dB S/N) FM (12 dB SINAD) 0.16 V*1 (1.8029.99 MHz) 0.13 V*2 (50 MHz) 0.11 V*3 (144 MHz) 13 V (0.51.799 MHz) 2 V*1 (1.8029.99 MHz) 1 V (50*2/144*3 MHz) 0.5 V*1 (28.029.99 MHz) 0.25 V*2 (50 MHz) 0.18 V*3 (144 MHz)

*1Pre-amp 1 is ON, *2Pre-amp 2 is ON, *3Pre-amp is ON Squelch sensitivity (Pre-amp: OFF):

SSB, CW, RTTY FM Less than 5.6 V Less than 1.0 V Selectivity

:

SSB (BW: 2.4 kHz) CW (BW: 500 Hz) RTTY (BW: 350 Hz) AM (BW: 6 kHz) FM (BW: 15 kHz) More than 2.4 kHz/6 dB Less than 3.6 kHz/60 dB More than 500 Hz/6 dB Less than 700 Hz/60 dB More than 360 Hz/6 dB Less than 650 Hz/60 dB More than 6.0 kHz/6 dB Less than 15.0 kHz/60 dB More than 12.0 kHz/6 dB Less than 20.0 kHz/60 dB Spurious and image rejection ratio:

HF/50 MHz 144 MHz AF output power

(at 13.8 V DC) RIT variable range PHONES connector Ext. SP connector More than 70 dB (except IF through on 50 MHz band) More than 60 dB

: More than 2.0 W at 10% distortion with an 8 load

: 9.99 kHz

: 3-conductor 6.35 (d) mm (14)

: 2-conductor 3.5 (d) mm (18)/8 Antenna tuner Matching impedance range:

HF bands 50 MHz band 16.7 to 150 unbalanced

(Less than VSWR 3:1) 20 to 125 unbalanced

(Less than VSWR 2.5:1) Minimum operating input power Tuning accuracy Insertion loss

: 8 W (HF bands) 15 W (50 MHz band)

: VSWR 1.5:1 or less

: Less than 1.0 dB (after tuning) All stated specications are typical and subject to change without no-

tice or obligation. 100 16 OPTIONS IC-PW1 HF/50 MHz ALL BAND 1 kW LINEAR AMPLIFIER PS-125 DC POWER SUPPLY Full-duty 1 kW linear amplier including an automatic antenna tuner. Has automatic tuning and band selection capability. Full break-in (QSK) oper-

ation is possible. The amplier/power supply unit and the remote control unit are separated. Light weight switching regulator system power supply. Output voltage: 13.8 V DC Max. current drain: 25 A AH-4 HF/50 MHz AUTOMATIC AH-2b ANTENNA ELEMENT SM-20 DESKTOP MICROPHONE ANTENNA TUNER A 2.5 m long an-

tenna element for mobile operation with the AH-4. Frequency coverage:

754 MHz bands with the AH-4 Specially designed to tune a long wire antenna for portable or mobile HF operation. The PTT tuner start function provides simple operation. Input power rating: 120 W SP-21 EXTERNAL SPEAKER CT-17 CI-V LEVEL CONVERTER Designed for base station opera-

tion. Input impedance: 8 Max. input power: 5 W For remote transceiver control using a personal computer. You can change frequencies, operating mode, memory channels, etc. Unidirectional, electret microphone for base station operation. Includes

[UP]/[DOWN] switches and a low cut function. UT-102 VOICE SYNTHESIZER UNIT Announces the receive frequency, mode and S-meter level in a clear, electroni-

cally-generated voice, in English (or Japanese). SP-20 EXTERNAL SPEAKER 4 audio lters; headphone jack; can con-

nect to 2 transceivers. Input impedance: 8 Max. input power: 5 W CR-338 HIGH STABILITY CRYSTAL UNIT Contains a temperature-compensating oven heater and crystal unit for improved frequency stability. Frequency stability: 0.5 ppm HM-36 HAND MICROPHONE Hand microphone equipped with

[UP]/[DOWN] switches. 101 A-6085H-1EX Printed in Japan 2001 Icom Inc. 1-1-32 Kamiminami, Hirano-ku, Osaka 547-0003 Japan

 

 

 

 

 

 

 

 

 

 

DC 13.8V 144MHz ANT ANT 2 ANT 1 IC-746PRO FCC ID:AFJ IC-746PRO MADE IN JAPAN GND TUNER KEY ACC(1) ACC(2) ALC SEND REMOTE EXT SP DATA HF/50MHz SERIAL NO. IC-746PRO

 

 

 

 

 

 

O Icom Inc. 6-9-16, Kamihigashi, Hirano-ku, Osaka, 547-0004, Japan.

| ( O M Phone : 06 6793 5302 Fax : 06 6793 0013 E-Mail: export@icom.co.jp Letter Of Agency December 1, 2001 American Telecommunications Certification Body, Inc. 6731 Whittier Avenue Suite C110 McLean, VA 22101 To Whom It May Concern:

Please be advised that Icom Incorporated authorizes Icom America Incorporated to act on our behalf, until otherwise notified, for applications submitted to American Telecommunications Certification Body, Inc. (ATCB). We certify that we are not subject to denial of federal benefits, that includes FCC benefits, pursuant to Section 5301 of the Anti-Drug Abuse ACT of 1988, U.S.C. 862. Further, no party, as defined in 47 CFR 1.2002(b), to the application is subject to denial of federal benefits, that includes FCC benefits. Thank you for your attention to this matter. Icom Incorporated TRA Takashi Aoki General Manager

 

 

Icom Inc. O 1-1-32, Kamiminami, Hirano-ku, Osaka, 547-0003 Japan

| Cc O M Phone : 06 6793 5302 Fax : 06 6793 0013 E-Mail: export@icom.co.jp November 24, 2001 Federal Communications Commission Authorization & Evaluation Division 7435 Oakland Mills Road Colombia, Maryland 21046 RE: Request for Confidentiality FCC ID: AFJ IC-746PRO Dear Sir/ Madam Please be advised that the following information is to be held confidential and behalf of Icom Inc.

* Block Diagram

* Schematic Diagram The application contains technical information which Icom Inc deems to be trade secrets and proprietary. If made public, the information might be used to the disadvantage of the applicant in the market place. Thank you for your attention to this matter. Sincerely Icom Incorporated _-

TK &

Takashi Aoki General Manager

 

 

Oo Icom Inc. 41-1-32, Kamiminami, Hirano-ku, Osaka, 547-0003 Japan

| ( O M Phone: 06 6793 5302 Fax: 06 6793 0013 E-Mail: export@icom.co.jp Manufactures Letter December 01, 2001 American Telecommunications Certification Body, Inc. 6731 Whittier Avenue Suite C110 McLean, VA 22101 RE: Certification Application FCC ID: AFJ IC-746PRO To Whom It May Concern:

Please be advised that the manufacture will ensure that the above-referenced model will be manufactured in accordance with the FCC Rules and Regulations. Thank you for your attention to this matter. ICOM Incorporated eh &

Takashi Aoki General Manager

 

 

O Icom Inc. 6-9-16, Kamihigashi, Hirano-ku, Osaka, 547-0004, Japan.

| ( O M Phone : 06 6793 5302 Fax : 06 6793 0013 E-Mail : export@icom.co.jp_ Application for Equipment Certification FCC Identifier AFJ IC-746PRO December 01, 2001 Scanning Receiver Statement for Compliance with 2.1033 (b) (12) The equipment under application herein incorporates a scanning receiver. Accordingly, 15.121 of the Commissions rules applies. The equipment under application herein is incapable of operating (tuning), or being readily altered by the user to operate within the frequency bands allocated to the Domestic Public cellular Radio Telecommunications Service (Cellular Radio Service). The equipment is also incapable of converting digital cellular transmissions to analog voice audio. The receiver portion of the equipment under application herein scans 108-174MHz, and the receiver does not scan the bands used by the Cellular Radio Service, 824-849 and 869-894MHz. The receiver portion of the equipment under application cannot be altered to enable it to scan the Cellular Radio Service bands by means of clipping the leads of or installing a diode, resistor and/or jumper wire, or other such simple component. Nor can the receiver be made to scan the Cellular Radio Service bans by replacing a plug-in semiconductor chip, since no such plug-in chips are utilized. The semiconductor chips that are utilized in the equipment cannot be erased and reprogrammed. The radio design of the tuning, control and filtering circuitry on the receiver is controlled by the serial data from the firmware code in the microprocessor, which is built-in by the microprocessor manufacture as a part of the internal design of the processor. Since the processor information is inaccessible to the user (Even Icom peoples), If the some one attempt modifying circuitry without the knowledge of the firmware code, the radio simply will fail to operate In view of the above, the equipment complies with 15.121 of the Commission rules. Sincerely Icom Incorporated

i) KL &

Takashi Aoki General Manager