29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 GIANT ELECTRONICS LTD. ALIGNMENT PROCEDURE For Cobra model CB 29 LX LE (Giant: 29-LX) MODEL: CB 29 LX LE REVISION: ___V01______ DATE : _2010-6-22___ PREPARED BY:___ CHECKED BY: ____________ APPROVED BY: ____________ Total page: 5 pages Page: 1 / 6 print date: 10-6-22 29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 CB 29-LX ALIGNMENT INSTRUCTION 13.8VDC CH19 / WX CH5 8 W 50 W 30% (AM) / WX +/- 3KHz (FM) 0.5W CH No. 1 2 3 4 5 6 7 8 9 10 CB Section: WX Section:
FREQ (MHz) 162.550 162.400 162.475 162.425 162.450 162.500 162.525 161.650 161.775 163.275 EXT.DC CB CB CB CB CB 1.0 TEST CONDITION:
1.1. STANDARD DC POWER:
1.2. MEASUREMENT CHANNEL:
1.3. STANDARD AUDIO LOADING:
1.4. ANTENNA IMPEDANCE:
1.5. STANDARD REF. MODULATION:
1.6. STANDARD REF. AUDIO OUTPUT:
1.7. FREQUENCY TABLE:
CH NO. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Above red color channels are the definition test model channel for alignment. FREQ. (MHz) 26.965 26.975 26.985 27.005 27.015 27.025 27.035 27.055 27.065 27.075 27.085 27.105 27.115 27.125 27.135 27.155 27.165 27.175 27.185 27.205 27.215 27.225 27.255 27.235 27.245 27.265 27.275 27.285 27.295 27.305 27.315 27.325 27.335 27.345 27.355 27.365 27.375 27.385 27.395 27.405 Page: 2 / 6 print date: 10-6-22 29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 1.8. TEST EQUIPMENT SETUP AS BELOW:
A. TX test equipment setup:
Spectrum Power Analyzer Supply Modulation Wattmeter CB29LTD Meter D.U.T. Oscilloscope Frequency Audio Gen. Counter Distortion AC Meter Voltmeter B. RX test equipment setup:
SINAD Meter RF Signal Power Generator Supply Distortion 8 ohm CB29LTD Meter loading D.U.T. Oscilloscope Note: D.U.T. = device under test Page: 3 / 6 print date: 10-6-22 29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 2.0 Alignment of P.L.L. portion of CB and WX. 2.1 Equipment required:
A: Oscilloscope B: DC voltage meter . Alignment procedure:
2.2 TEST ITEM 1. CB TX VCO voltage TEST CONDITION & PROCEDURE Connect the DC volt. Meter to the
@ CH40 junction point of R59 and R60. 1. CB TP3 OUTPUT Connect the oscilloscope to the junction
@ TX mode point of R6 and JP14. 2. WX VCO voltage
@ CH8 / CH10 Connect the DC volt. Meter to the TP601 PURPOSE Adjust L19 to obtain approximately 3.0V 0.2V reading. Adjust L20 for maximum output on the oscilloscope. 1. Adjust L605 to obtain approx 1.5 0.1V
@CH8 (162.650MHz) 2. Checking the CH10 the volt 3.0V 3.0 Alignment of CB receiver portion. 3.1 Equipment required:
A: Signal generator B: AC voltmeter. C: Oscilloscope. D: Dummy load ( 8 ohm, 5 watts, resistive.) E: DC power supply ( 13.8 v. 2Amp.) 3.2 Alignment procedure:
TEST ITEM 1. AUDIO OUTPUT 2. RX Sensitivity 3. NB 4.Tight Squelch 5. S-9 and +30 meter indicator. TEST CONDITION & PROCEDURE 1. Set channel 19. 2. Set the S.G. on 27.185MHz with 1KHz, 30% mod. and 1mV output level. 3. Set NB/OFF SW to OFF, Squelch to min.
( CCW), CB/WX/PA to CB, ANL SW to CB/ANL, RF GAIN to max. Volume approximately Center. 1. Same as above step 1 and 3. 2. Set the S.G. on 27.185MHz with 1KHz, 30% mod. RF output level 1.0uV. 1. Set NB/OFF SW to NB. 2. Set the level of S.G. to 1.0uV. 3. Noise generator to on. 4. Adjusted then revert item 1 setup. 1. Set Squelch volume to maximum ( CW ). 2. Set the level of S.G. to 1500uV. 3. Adjusted then revert item 1 setup. 1. Set the level of S.G. to 100uV. 2. Set the level of S.G. to 3.16mV. 6. PA output RF Level
@1mV, 30% Mod. 1. Set CB/WX/PA to PA function PURPOSE 1. Adjust L1,2,3,4,5,6 & 7 for maximum audio output & minimum distortion on the distortion meter. 1. Adjust L1,2,3,4,5,6 &7 for more than 12dB to the SINAD meter. 2. Repeat as needed. 3. Set RF S.G. output level 0.4uV, the adj. VR2 to 2V on the AC volt meter. 1. Turn the volume to obtain 2V reading on AC voltmeter. 2. Adjust L1 for minimum reading on AC volt meter. 1. Slowly turn VR4 to a position that the audio output waveform at the scope just appears from no output. 1. Adjust VR1 for S-9 reading on The LCD meter. 2. Check the bars up to +30. 1. Checking the audio output need more than 3.5W @10%THD Page: 4 / 6 print date: 10-6-22 29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 4. Alignment of WX receiver portion. 4.0 Equipment required:
A: Signal generator B: AC voltmeter. C: Oscilloscope. D: Dummy load ( 8 ohm, 5 watts, resistive.) E: DC power supply ( 13.8 v. 2Amp.) 4.1 Alignment procedure:
TEST ITEM 1. AUDIO OUTPUT 2. RX Sensitivity TEST CONDITION & PROCEDURE 1. Set channel 5. RF connect to the TP4. 2. Set the S.G. on 10.7MHz with 1KHz, 3KHz mod. and 1mV output level. 3. CB/WX/PA to WX. Volume set approximately Center. 1. Set RF output connect to the TP1. 2. Set the S.G. on 162.450MHz with 1KHz, 3KHz mod. RF output level 1.0uV. 1. Set unit off, RF output @1.2uV, AF
@1050Hz, RF Freq @162.450MHz 3. Tone Decoder Sens.
(Turn-on): @4KHz 5. Alignment of Transmitter portion. 5.1 Equipment Required:
PURPOSE 1. Adjust L604 for maximum 2. audio output & minimum distortion on the distortion meter. 1. Adjust L603 & L602 for more than 12dB to the SINAD meter. Repeat as needed. 1. The unit will turn on automatically when RF signal open. A: VTVM ( full scale: 1V DC with RF probe). B: RF power meter. C: Spectrum analyzers. D: Frequency counter. E: DC power supply. (13.8VDC / 3AMPs) F: 50 ohm load and attenuator. G: Oscilloscope. H: AF generator. 5.2 Alignment procedure:
TEST ITEM 1. TP4 output 2. TX power TEST CONDITION & PROCEDURE 1. Connect the oscilloscope to the TP4. 2. Set TX mode , Channel 19. 1. Set TX Channel 19. 3. TX carrier frequency 1. Set TX Channel 19. 4. Second harmonic 1. Set TX Channel 19. 5. P4 indicator 1. Set TX Channel 19. 6. Modulation 7. Talk-back 1. Set TX Channel 19. 2. AF GEN. Output 30mV. 1. Set unit in TX mode with 90% Mod. PURPOSE Adjust L20, 21, 17 for maximum output on the oscilloscope. 1. Adjust L17,14 for maximum output on the RF power meter. 2. Turn L14 to obtain 4.0W on the RF meter reading. 1. Adjust L24 to obtain 27.185MHz on the frequency counter. 1. Adjust L11 for a min. 2nd harmonic
( 54MHz) output on the Spectrum anal. 1. Adjust VR5 for P4 display at the TX Signal meter of the LCD meter. 1. Adjust VR4 for 90% on the modulation Meter. 1. The speaker can be heard the tone when Talkback turn on. Page: 5 / 6 print date: 10-6-22 29-LX ALIGNMENT REVISION: 00 ENG-29-LX-08 5. LCD & Backlight Checking 5.1 There are four colors in the backlighting operation, they are Red, Green, Blue and Amber. 5.2 The LCD drawing as following display in dot matrix and icons. 5.3 Please refer to the next procedure of item 6 let the UUT into the test mode to checking the LCD and backlight performance. 6. Test Mode Operating Method 6.1 Press and hold the key of CB/WX/PA and Enter at the same time then turn the DC power on to enter the test mode for CB and WX channel. 6.2 In CB mode, turn the channel selector by clockwise for CH1 (26.965MHz) CH19 (27.185MHz) CH22 (27.225MHz) CH40 (27.405MHz). 6.3 In WX mode, turn the channel selector by clockwise for CH8 (161.650MHz) CH5 (162.450MHz) CH10 (163.275MHz). 6.4 Press the NB/ANL key for LCD display scanning 6.5 Press the SWR/CAL key for backlight Amber color turn on; Press the MEM SCAN key for backlight RED color turn on; Press the CH9/19 key for backlight Green color turn on; Press the DIM/ESC key for backlight Blue color turn on. 7. Radio Check 7.1 Battery Check: In radio check menu mode, select 1ST Test Battery Level. BATTERY VOLTAGE PASS: 11.2VDC 15.5VDC FAIL HIGH: 15.5V 16.5V FAIL LOW: 10V 11.2V 7.2 RF Power Check: In radio check menu mode, select 2nd Test RF POWER OUTPUT. RF POWER OUTPUT PASS: TX Power more than 3.0W @50 ohm loading FAIL: TX Power less than 3.0W @50 ohm loading 7.3 Antenna Mismatch Warning Check: In radio check menu mode, select 3rd Test CHECK ANTENNA. PASS: @50 ohm dummy loaded FAIL: Antenna open or Shorted. Page: 6 / 6 print date: 10-6-22