FCC ID: M3UWRCTX Wireless Rain-Clik Rain Sensors

INTRODUCTION In most installations, the Wireless Rain-Clik acts as a switch to break the circuit to the solenoid valves of the irrigation system when it has rained. This allows the timer to advance as scheduled, but keeps the valves from opening the water flow. Once the Wireless Rain-Clik has dried sufficiently, the switch closes again to allow for normal operation. MOUNTING Standard Mount:

Using the screws provided, mount the Wireless Rain-Clik transmitter on any surface where it will be exposed to unobstructed rainfall, but not in the path of sprinkler spray. The switch-housing portion must be upright (as pictured), but the swivel-bracket can be moved for mounting on any angled surface. Gutter Mount:

Clip the enclosed gutter mounting bracket over the inside lip of the gutter. Attach the Wireless Rain-Clik to the gutter mounting bracket with the screws provided. Helpful Hints for Mounting:

A. When looking for a suitable location such as on the side of a building or post, the closer the Wireless Rain-Clik is to the controller, the better reception will be. DO NOT EXCEED 300 feet. B. The ideal location for mounting is not always the most practical location. In the case where a compromise must exist (such as low location on a side wall rather than the preferred high location), note that the Wireless Rain-Clik will still work as it will always receive some rainfall it just will not be as accurate in its gauging as it could be. C. As described in the Operation section of this manual, reset rate refers to the amount of time it takes the Wireless Rain-

Clik to dry out sufficiently for the sprinkler system to be allowed to come back on. The mounting location will affect this rate and should be taken into consider-

ation should extreme conditions exist. For example, mounting the Wireless Rain-Clik on a very sunny, southern end of a building may cause the Wireless Rain-Clik to dry out sooner than desired. Similarly, mounting on the northern end of a building with constant shade may keep the Wireless Rain-Clik from drying soon enough. Transmitters/Sensor Nothing to set up with this unit after installation The unit can be tested stand-alone as follows:

press and hold the post on the quick response section. Within 3 seconds of pressing and holding this post down, the LED protruding from the potting should blink once. Release the post, within 3 seconds the LED should blink once again. (Figure 1) Standard Mount Gutter Mount Manually depress the spindle at the top of the Wireless Rain-ClikTM Figure 1 Wireless Rain-ClikTM Rain Sensors Installation Instructions WIRING TO YOUR IRRIGATION SYSTEM Important: The Wireless Rain-Clik is sold and designed for hook up to 24 Volt irrigation controllers only. WARNING! This unit is designed to be installed in conjunction with 24VAC circuits only. Do not use with 110 or 220VAC circuits. Receiver Installation, SRC Controller:

1. Using the hardware included, mount the receiver to the wall (use included wall anchors if needed). Make sure to put the rubber cover/gasket under the unit when attaching it in an outdoor location. 2. Attach the two yellow wires to the AC terminals of the SRC (polarity does not matter). Hunter SRC AC AC R RS C 1 2 3 VALVES Wireless Rain Sensor SENSOR BYPASS SENSOR STATUS WIRELESS RAIN SENSOR Red light indicates sensor is bypassed GREEN = Sensor is dry RED = Sensor is wet Press to bypass, press again to re-enable RAIN SENSOR BYPASS Y Y B W Figure 2 3. Attach the blue wire to the RS terminal. 4. Attach the white wire to the C terminal. 5. Attach the valve common wire to the RS terminal. Receiver Installation, Pro-C and ICC Controllers:

1. Using the hardware included, mount the receiver to the wall (use included wall anchors if needed). Make sure to put the rubber cover/gasket under the unit when attaching it in an outdoor location. 2. Attach the two yellow wires to the AC terminals of the controller (polarity does not matter). 3. Attach the blue wire to one SEN terminal and the white wire to the other SEN terminal of the controller. Wireless Rain Sensor SENSOR BYPASS SENSOR STATUS WIRELESS RAIN SENSOR Red light indicates sensor is bypassed GREEN = Sensor is dry RED = Sensor is wet Press to bypass, press again to re-enable RAIN SENSOR BYPASS Hunter ICC C P MV SEN SEN TEST REM AC AC G B W Y Y Figure 3 A. Receiver Installation, Other Controllers:

1. Using the hardware included, mount the receiver to the wall (use included wall anchors if needed). Make sure to put the rubber cover/gasket under the unit when attaching it in an outdoor location. 2. Attach the two yellow wires to the AC terminals of the controllers (polarity does not matter). 3a. Most controllers use a normally closed rain sensor. To attach the receiver to this type of controller, attach the blue wire and the white wire to the sensor terminals of the controller, or in-line with the valve common. 3b. A few controllers on the market require a normally open rain sensor. To attach the receiver to this type of controller, attach the blue wire and the orange wire to the controllers sensor input. Wireless Rain Sensor SENSOR BYPASS SENSOR STATUS WIRELESS RAIN SENSOR Red light indicates sensor is bypassed GREEN = Sensor is dry RED = Sensor is wet Press to bypass, press again to re-enable RAIN SENSOR BYPASS Controller C P MV AC AC Common Wire to all Valves W B Y Y Figure 4 Wireless Rain-ClikTM Rain Sensors Installation Instructions Controller C 1 2 3 4 B. 24 Volt Solenoid Valves Pump or MV AC AC Line-In with Booster Pump

(See Figure 5) Locate the common wire to the solenoid valves and the common wire leading to the coil of the relay that starts the pump. If these two wires are connected to the common terminal on the controller, disconnect both of them. Twist together these two wires along with one wire from the Rain-Clik, and secure with a wire nut. Attach the other wire of the Wireless Rain-Clik receiver to the common terminal on the controller. Note: The pump circuit output must be 24 Volts in this situation. Do not proceed if 110V. Normally-

Open Relay Line-Out (to Pump) Figure 5 Common Wire to All Valves Wireless Rain Sensor SENSOR BYPASS SENSOR STATUS WIRELESS RAIN SENSOR Red light indicates sensor is bypassed GREEN = Sensor is dry RED = Sensor is wet Press to bypass, press again to re-enable RAIN SENSOR BYPASS Y Y W B Solenoid Valves Learning the transmitter address at the receiver:

Units purchased as a kit will already have their address learned. Each transmitter produced has a unique address hard-coded into it. A receiver must learn this address to work with that transmitter. This step will only be necessary if transmitters and receivers are purchased separately. 1. Prior to applying power (yellow wires) to the receiver, press and hold the receivers pushbutton. 2. While the pushbutton is being held apply power to the receiver the receivers sensor status LED should light up yellow indicating the receiver is ready to learn an address. 3. Push and hold the quick response post on the transmitter/sensor. 4. Within 4 seconds, the receivers sensor status LED should turn red. 5. Release the transmitter/sensors quick response post and within 4 seconds the LED on the receiver should turn green. The address is now learned and will be retained even in the event of a power outage. OPERATION Once the receiver and transmitter have been installed and the receiver has learned the transmitter's address, the system is ready to work. The receiver has two LEDs, which indicate the state of the system. The STATUS LED will be RED when the sensor is wet (watering disabled), and GREEN when the sensor is dry

(watering enabled). There is also a RED BYPASS LED on the receiver. If this LED is lit, the rain sensor is bypassed and watering will always be allowed. Even though the sensor is bypassed, the STATUS LED will continue to alert you of the state of the sensor (Wet or Dry). If the communication between the transmitter and the receiver ever breaks down, the transmitters status LED will flash red. Figure 6 ADJUSTMENTS AND OPERATION The Wireless Rain-Clik can keep the irrigation system from starting or continuing after rainfall. The time that it takes the Wireless Rain-Clik to reset for normal sprinkler operation after the rain has stopped is determined by weather conditions (wind, sunlight, humidity, etc.) These conditions will determine how fast the hydroscopic discs dry out, and since the turf is also experiencing the same conditions, their respective drying rates will roughly parallel each other. So when the turf needs more water, the Rain-Clik is already reset to allow the sprinkler system to go at the next scheduled cycle. There is an adjustment capability on the Wireless Rain-Clik that will slow down the reset rate. By opening the vent (see Figure 6) to completely or partially cover the ventilation slots, the hydroscopic discs will dry more slowly. This adjustment can compensate for an overly sunny installation location, or peculiar soil conditions. Experience will best determine the ideal vent setting. Vent Ring Vents BYPASSING THE SENSOR The sensor may be bypassed by using the built in bypass feature in the SRC, Pro-C or ICC. On other controllers the sensor may be bypassed by pressing the BYPASS button on the receiver. The RED BYPASS LED on the receiver will be lit when the sensor is bypassed. Pressing the BYPASS button again will cause the RED BYPASS LED to go back out thus re-enabling the sensor. Battery Life: The Wireless Rain-Clik transmitter is designed to work daily for up to ten years with the original battery. The sealed unit is available as a replacement part. Should you need to change the transmitter the receiver will have to learn the new transmitter address. There is no required maintenance for the unit. The Wireless Rain-Clik does not have to be removed or covered for winterizing purposes. TROUBLESHOOTING Follow these simple checks first before assuming the unit is bad and replacing it. System will not come on at all:

A. First, check to see that the Wireless Rain-Clik discs are dry and the switch clicks on and off freely by pressing the top of the spindle. B. Next, look for breaks in the wire leading to the Wireless Rain-Clik receiver and check all wire junctions. System will not shut off even after heavy rainfall:

A. Check wiring for correctness (see Operation Check to Verify Correct Wiring). B. Is the rainfall actually hitting the Wireless Rain-Clik? Check for obstructions to rainfall such as overhangs, trees or walls. Manufactured under U.S. Patent Pending All Rain-ClikTM models are listed by Underwriters Laboratories, Inc. (UL). Samples of these devices have been evaluated by UL and meet the applicable UL standards for safety. For information on the complete line of Hunter products, visit our Web site at www.HunterIndustries.com FCC Compliance Notice This device complies with FCC rules Part 15. Operation is subject to the following two conditions:

1) This device may not cause harmful interference and 2) This device must accept any interference that may be received, including interference that may cause undesired operation Transmitter FCC ID: M3UWRCTX Hunter Industries Incorporated The Irrigation Innovators U.S.A.: 1940 Diamond Street San Marcos, California 92069 TEL: (1) 760-744-5240 FAX: (1) 760-744-7461 www.HunterIndustries.com 2002 Hunter Industries Incorporated 23-461 4/02

TXM-315-LC TXM-418-LC TXM-433-LC LC SERIES TRANSMITTER MODULE DATA GUIDE DESCRIPTION:

PHYSICAL DIMENSIONS The LC Series is ideally suited for volume use in OEM applications such as remote control, security, identification, and periodic data transfer. Packaged in a compact SMD package, the LC transmitter utilizes a highly optimized SAW architecture to achieve an unmatched blend of performance, size, efficiency and cost. When paired with a matching LC series receiver, a highly reliable wireless link is formed, capable of transferring serial data at distances in excess of 300 Feet. No external RF components, except an antenna, are required, making design integration straightforward, even for engineers lacking previous RF experience. 360

.500 TOP VIEW FEATURES:

I Low Cost I No External RF Components Required I Ultra-low Power Consumption I Compact Surface-Mount Package I Stable SAW-based Architecture APPLICATIONS INCLUDE:

I Remote control I Keyless entry I Garage / Gate openers I Lighting control I Medical monitoring / Call systems I Remote industrial monitoring I Periodic data transfer I Home / Industrial automation I Fire / Security alarms I Remote status / Position sensing I Long-range RFID I Wire Elimination PINOUTS I Supports Data Rates to 5,000 bps I Wide Supply Range (2.7-5.2 VDC) I Direct Serial Interface I Low Harmonics I No Production Tuning ORDERING INFORMATION PART # DESCRIPTION Basic Evaluation Kit EVAL-***-LC Master Development Kit MDEV-***-LC TXM-315-LC Transmitter 315 MHZ Transmitter 418 MHZ TXM-418-LC Transmitter 433 MHZ TXM-433-LC Receiver 315 MHZ RXM-315-LC RXM-418-LC Receiver 418 MHZ RXM-433-LC Receiver 433 MHZ

*** Insert Frequency Not covered in this manual LC Transmitters are supplied in tube packaging - 50 pcs. per tube. Revised 12/21/01 PERFORMANCE DATA TXM-***-LC ABOUT THESE MEASUREMENTS The performance parameters listed below are based on module operation at 25C from a 3.3Vdc supply unless otherwise noted. Figure 1 at the right illustrates the connections necessary for testing and operation. It is recommended that all ground pins be connected to the groundplane. figure 1: Test/Basic application circuit Parameters LCTX 433, 418, 315MHz Operating Voltage Range Current Continuous Current Average Current In Sleep Data Input Low Data Input High Oscillator Start-up Time Oscillator Ring-down Time Output Power Designation Min. 2.7 0 2.5

-4 VCC ICC ICA ISLP VIL VIH TOSU TORD PO Typical 3.0 1.5 0 Max. 5.2 6.0 1.5 0.4 VCC 80 100

+4 Units Volts mA mA A Volts Volts S nSec dBm Parameter LCTX 315MHz Frequency of Carrier Harmonic Emissions Parameter LCTX 418MHz Frequency of Carrier Harmonic Emissions Parameter LCTX 433MHz Frequency of Carrier Harmonic Emissions Designation Min. 314.925 Typical 315.0 Max. Units 315.075 MHz

-40 dBc Designation Min. Typical 417.925 418 Max. Units 418.075 MHz

-40 dBc Designation Min. 433.845 Typical 433.92 Max. Units 433.995 MHz

-45 dBc FC PH FC PH FC PH Notes 1, 5 2, 5 3 4 4 4 Notes 4 Notes 4 Notes 4 Notes:

1. Current draw with data pin held continuously high. 2. Current draw with 50% mark/space ratio. 3. Current draw with data pin low. 4. RF out connected to 50 load. 5, Ladj (pin 4) through 430 resistor. Page 2 Absolute Maximum Ratings:

Supply voltage VCC, using pin 7 Operating temperature Storage temperature Soldering temperature Any input or output pin

+8

+7

+6

+5

+4

+3

+2

+1 0

-1

-2

-3

-4

-5

-6

*NOTE* Exceeding any of the limits of this section may lead to

-7 permanent damage of the device. Furthermore, extended operation at these maximum ratings may reduce the life of this device.

+6 VDC

+70C

+85C

-0.3

-30C

-45C

+225C for 10 sec. SUPPLY VOLTAGE to to to VCC

-0.3 to 3.5 4.0 4.5 5.0 2.5 3.0

(V) TYPICAL PERFORMANCE GRAPHS 12 11 10 9 8 7 6 5 4 3 2 1 0

) A m

(

t n e r r u C y p p u S l 2.5 3.0 3.5 4.04.0 4.54.5 5.0

(V)

(V) SUPPLY VOLTAGE SUPPLY VOLTAGE With Iadj tied to ground With 430 resistor at Iadj (pin) figure 2: Consumption vs. Supply Voltage p g r e w o P t u p t u O

+8+8

+7+7

+6+6

+5+5

+4+4

+3+3

+2

+1+1 0

-1

-2

-3

-4

-5

-6

-7 m B d 2.5 3.0 3.5 4.0 4.54.5 5.0

(V) SUPPLY VOLTAGE SUPPLY VOLTAGE With Iadj tied to ground With 430 resistor at Iadj (pin) figure 3: Typical RF power into 50 figure 4: Typical Oscillator Turn-On Time figure 5: Typical Oscillator Turn-Off Time Data Carrier Data Carrier 12 11 10 9 8 7 6 5 4 3 2 3.5 1 0 2.5 3.0 4.0 4.5 5.0

(V) SUPPLY VOLTAGE Page 3 TRANSMITTER AUTOMATED ASSEMBLY PRODUCTION GUIDELINES For high-volume assembly most users will want to auto-place the modules. The modules have been designed to maintain compatibility with most pick-and-place equipment; however, due to the module's hybrid nature certain aspects of the automated assembly process are far more critical than for other component types. Following are brief discussions of the three primary areas where caution must be observed. Reflow Temperature Profile The single most critical stage in the automated assembly process is the reflow process. The reflow profile below should be closely followed since excessive temperatures or transport times during reflow will irreparably damage the modules. Assembly personnel will need to pay careful attention to the oven's profile to insure that it meets the requirements necessary to successfully reflow all components while still meeting the limits mandated by the modules themselves. Shock During Reflow Transport Since some internal module components may reflow along with the components placed on the board being assembled, it is imperative that the module not be subjected to shock or vibration during the time solder is liquidus. 300 C 250 200 Temperature 150 100 50 0 Ideal Curve Limit Curve Forced Air Reflow Profile 220C 210C 180C 125C Reflow Zone Soak Zone 20-40 Sec. 2 Minutes Max. Preheat Zone 2-2.3 Minutes Ramp-up 1-1.5 Minutes Cooling 0 30 60 90 120 150 180 210 240 270 300 330 360 Time (Seconds) figure 6: Required reflow profile Washability The modules are wash resistant, but are not hermetically sealed. They may be subject to a standard wash cycle; however, a twenty-four-hour drying time should be allowed before applying electrical power to the modules. This will allow any moisture that has migrated into the module to evaporate, thus eliminating the potential for shorting during power-up or testing. The LC modules are packaged in a hybrid SMD package which has been designed to support hand- or automated-assembly techniques. Since LC devices contain discrete components internally, the assembly procedures are critical to insuring the reliable function of the LC product. The following procedures should be reviewed with and practiced by all assembly personnel. PAD LAYOUT The following pad layout diagrams are designed to facilitate both hand and automated assembly. TX Layout Pattern Rev. 2

(Not to Scale) 0.100"

0.310"

0.100"

0.070"

LC-P RX Layout Pattern Rev. 3 Pinned SMD Version LC-S RX Layout Rev. 1 Compact SMD Version

(Not to Scale) 0.150 0.775

.100

.070

(Not to Scale) 0.065"

0.610"

0.100"

0.070"

figure 7: Suggested Pad Layout TRANSMITTER HAND ASSEMBLY The LC transmitter's primary mounting surface is eight pads located on the bottom of the module. Since these pads are inaccessible during mounting, castellations that run up the side of the module have been provided to facilitate solder wicking to the module's underside. If the recom-

mended pad placement (Rev.2) has been followed, the pad on the board will extend slightly past the edge of the module. Touch both the PCB pad and the module castellation with a fine soldering tip. Tack one module corner first, then work around the remaining attachment points using care not to exceed the solder times listed below. Soldering Iron Tip Solder PCB Pads Castellations Figure 8: LC-TX Soldering Technique Absolute Maximum Solder Times Hand-Solder Temp. TX +225C for 10 Sec. Hand-Solder Temp. RX +225C for 10 Sec. Recommended Solder Melting Point +180C Reflow Oven: +220 Max. (See adjoining diagram) Page 4 Page 5 PHYSICAL PACKAGING MODULE DESCRIPTION The transmitter is packaged as a hybrid SMD module with eight pads spaced 0.100" apart on center. The SMD package is equipped with castellations which allow for side introduction of solder. This simplifies prototyping or hand assembly while maintaining compatibility with automated pick-and-place equipment. Modules are available in tube or tape-and-reel packaging (see page 1 for ordering information). PIN DESCRIPTIONS:

Pin 1 GROUND Connect to quiet ground or groundplane. Pin 2 DATA IN Serial data input pin. TTL and CMOS compatible. Pin 3 GROUND Connect to quiet ground or groundplane. Pin 4 LADJ/GND Output power level adjustment. Connect to ground for 3V operation. Connect to ground through 430 Ohm resistor for 5V operation. (see graph on page 3 and page 10) Pin 5 RF OUT Connect to 50 matched antenna. Pin 6 GROUND Connect to quiet ground or groundplane. Pin 7 POSITIVE SUPPLY (Vcc 2.7-6 VDC) TOP VIEW

.365

.505 SIDE VIEW

.150 Max. 042

.290

.103.103 BOTTOM VIEW 1 2 3 4

.060 x .060 Typ. 8 7 6 5

.100 (Typ.) figure 9: LC -TXM Physical Package The supply must be clean (<20 mV pp), stable and free of high-frequency noise. A supply filter is recommended unless the module is operated from its own regulated supply or battery. Pin 8 GROUND Connect to quiet ground or groundplane. POWER SUPPLY REQUIREMENTS The transmitter module requires a clean, well-

regulated power source. While it is preferable to power the unit from a battery, the unit can also be operated from a power supply as long as noise and hash are kept to less than 20 mV. A 10 resistor in series with the supply followed by a 10F tantalum capacitor from Vcc to ground as shown at the right will help in cases where the quality of supply power is poor. Page 6 10R figure 10: Supply Filter The LC-TXM is a low-cost, high-performance SAW-(Surface Acoustic Wave) based CPCA (Carrier-Present Carrier-Absent) transmitter capable of sending serial data at up to 5,000 bits/second. The LCs compact surface-mount package integrates easily into existing designs and is equally friendly to prototype and volume production. The LCs ultralow power consumption makes it ideally suited for battery powered products. When combined with a Linx LC series receiver a reliable RF link capable of transferring data over line-of-sight distances in excess of 300 feet (90M) is formed. 50 RF OUT

(Ant.) Keyed Output SAW Oscillator Vcc Data In 300-5000 BPS Output Isolation

& Filter RF Amplifier figure 11: LC Series Transmitter Block Diagram THEORY OF OPERATION The LC-TXM transmits data using CPCA (Carrier-Present Carrier-Absent) modulation. This type of AM modulation is often referred to by other designations including CW and OOK. This type of modulation represents a logic low 0 by the absence of a carrier and a logic high 1 by the presence of a carrier. This modulation method affords numerous benefits. Three of the most important are: 1) Cost-

effectiveness due to design simplicity. 2) No minimum data rate or mark/space ratio requirement. 3) Higher output power and thus greater range in countries (such as the US) where output power measurements are averaged over time. (Please refer to Linx application note #00130). The LC-TXM is based on a simple but highly optimized architecture which achieves a high fundamental output power with low harmonic content. This insures that most approval standards can be met without external filter components. The LC transmitter is exceptionally stable over time, temperature, and physical shock as a result of the precision SAW (Surface Acoustic Wave) frequency reference. Due to the of the SAW device most of the output power is concentrated in a narrow bandwidth. This allows the receivers pass opening can be quite narrow, thus increasing sensitivity and reducing susceptibility to near-band interference. The quality of components and overall architecture utilized in the LC series is unusual in a low-cost RF device and is one reason the LC transmitter is able to outperform far more expensive products. THE DATA INPUT A CMOS/TTL level data input is provided on pin 2. This pin is normally supplied with a serial bitstream input directly from a microprocessor, encoder, or UART. During standby or the input of a logic low, the carrier is fully suppressed and the transmitter consumes less than 2A of current. During a logic high the transmitter generates a carrier to indicate to the receiver the presence of a logic 1. The applied data should not exceed a rate of 5,000 bits/sec. The data input pin should always be driven with a voltage common to the supply voltage present at pin 7 (Vcc). The data pin should never be allowed to exceed the supply voltage (Vcc). Page 7 TRANSMITTING DATA BOARD LAYOUT CONSIDERATIONS Once a reliable RF link has been established, the challenge becomes how to effectively transfer data across it. While a properly designed RF link provides reliable data transfer under most conditions, there are still distinct differences from a wired link that must be addressed. Since the LC modules do not incorporate internal coding/decoding, a user has tremendous flexibility in how data is formatted and sent. It is always important to separate what type of transmissions are technically possible from those that are legally allowable in the country of intended operation. You may wish to review application notes #00125 and #00140 along with Part 15 Sec. 231 for further details on acceptable transmission content. Another consideration is that of data structure or protocol. If you are not familiar with the sending serial data in a wireless environment read Linx application note #00232

(Considerations for sending data with the LC series). This application note details important issues such as the effect of start-up times, pulse stretching and shortening and the relationship between data and output power in a CPCA-based transmitter. These issues should be understood prior to commencing a design effort. If you want to send simple control or status signals such as button presses or switch closures, consider using an encoder and decoder IC set available from a wide range of manufacturers including: Microchip (Keeloq), Holtek, and Motorola. These ICs take care of all encoding, error checking, and decoding functions and generally provide a number of data pins to which switches can be directly connected. Address bits are usually provided for security and to allow the addressing of multiple receivers independently. Additionally, it is a simple task to interface with inexpensive microprocessors such as the Microchip PIC or one of many IR, remote control, DTMF, and modem ICs. Shown below is an example of a basic remote control transmitter utilizing a encoder chip from Holtek. When a key is pressed at the transmitter, a corresponding pin at the receiver goes high. A schematic for the receiver/decoder circuit may be found in the LC receiver guide. is integration If you are at all familiar with RF devices you may be concerned about specialized board layout requirements. Fortunately, because of the care taken by Linx in designing the LC series, very straightforward. This ease of application results from the advanced multi-layer construction of the module. By adhering to the layout principles and observing a few basic design rules, you can enjoy a straightforward path to RF success. 1. A groundplane should be placed under the module as shown. It will generally be placed on the bottom layer. The amount of overall plane is also critical for the correct function of many antenna styles and is covered in the next section. figure 13: Example of proper GROUNDPLANE ON BOTTOM LAYER groundplane following 2. Observe appropriate layout practice between the module and its antenna. A simple trace may suffice for runs of less than .25" but longer distances should be covered using 50 coax or a 50 microstrip transmission line. In order to minimize loss and detuning, a microstrip transmission line is commonly utilized. The term microstrip refers to a PCB trace running over a groundplane, the width of which has been calculated to serve as a 50 transmission line. This effectively removes the trace as a source of detuning. The correct trace width can be easily calculated using the information below.The width is based on the desired characteristic impedance, the thickness of the PCB, and its dielectric constant. figure 12: Basic Remote Control Transmitter Circuit Notes:

1) DIP Switch used to set ID code. A 3-position switch was chosen for this example but all or none of the address bits may be used. Settings of the Receiver and Transmitter must match for signal to be recognized. Page 8 figure 14: Microstrip formulas (Er = Dielectric constant of pc board material) Dielectric Constant 4.8 4 2.55 Width/Height

(W/d) 1.8 2 3 Effective Dielectric Characteristic Constant Impedance 3.59 3.07 2.12 50.0 51.0 48.0 Page 9 3. Depending on the type of antenna being used and duty cycle of incoming data, the output power of the LC module may be higher than FCC regulations allow. The output power of the module is intentionally set high since many designers pair the module with an inefficient antenna in order to realize cost or space savings. Since attenuation is often required it is generally wise to provide for its implementation. Two methods of attenuation are available using the LC module. First, a resistor may be placed in series with Pad 4 (LVL. ADJ.) to achieve up to a 7 dB reduction in output power. The resistor value is easily determined from the diagram below. Do not exceed the resistance values shown as transmitter instability may result. This method can also be used to reduce transmission range and power consumption.

+8

+7

+6

+5

+4

+3

+2

+1 0

-1

-2

-3

-4 m B d r e w o P t t u p u O 5V 3V 51 100 150 200 240 300 360 430 510 560 620 680 750 820 910 1.1K LADJ Pin Resistor Value figure 15: Power Output vs. LADJ Pad Resistor Value Another method commonly used to achieve attenuation, particularly at higher levels, is the use of a T-pad. A T-pad is a 3-resistor network that allows for variable attenuation while maintaining the quality of match to the antenna. It is usually prudent to allow space for the addition of a T-pad. For further details on T-pads please refer to Linx application note #00150. CIRCUIT TYPICAL LAYOUT WITH PROVISION FOR ATTENUATION PADS FOR SMT PADS FOR SMT RESISTORS RESISTORS ANT. ANT. R1 R1 R2 GND ANT. OUT GR OUNDPLANE GROUNDPLANE GR ON LOWER LAYER YER ON LO WER LA ON LO OUNDPLANE WER LA YER GR OUND OUND GROUND GR GROUND GR GR OUND OUND ANTENNA CONSIDERATIONS The choice of antennas is one of the most critical and often overlooked design considerations. The range, performance, and legality of an RF link is critically dependent upon the type of antenna employed. Proper design and matching of an antenna is a complex task requiring sophisticated test equipment and a strong background in principles of RF propagation. While adequate antenna performance can often be obtained by trial and error methods, you may also want to consider utilizing a professionally designed antenna such as those offered by Linx. Our low-

cost antenna line is designed to ensure maximum performance and compliance with Part 15-attachment requirements. The purpose of the following sections is to give you a basic idea of some of the considerations involved in the design and selection of antennas. For a more comprehensive discussion please review Linx applications note #00500 Antennas: Design, Application, Performance. THE TRANSMITTER ANTENNA The transmitter antenna allows RF energy to be efficiently radiated from the output stage into free space. In modular designs such as the LC, a transmitters output power is often slightly higher than the legal limit. This allows a designer to utilize an inefficient antenna in order to achieve full legal power while meeting size, cost, or cosmetic objectives. For this reason a transmitter's antenna can generally be less efficient than the antenna used on the receiver. It is usually best to utilize a basic 1/4-wave whip for your initial concept evaluation. Once the prototype product is operating satisfactorily, a production antenna should be selected to meet the cost, size and cosmetic requirements of the product. Maximum antenna efficiency is always obtained when the antenna is at resonance. If the antenna is too short, capacitive reactance is present; if it is too long, inductive reactance will be present. The indicator of resonance is the minimum point in the VSWR curve. You will see from the following example that antenna (A) is resonant at too low a frequency, indicating excessive length, while antenna (C) is resonant at too high a frequency, indicating the antenna is too short. Antenna (B), however, is just right. Antenna resonance should not be confused with antenna impedance. The difference between resonance and impedance is most easily understood by considering the value of VSWR at its lowest point. The lowest point of VSWR indicates the antenna is resonant, but the value of that low point is determined by the quality of the match between the antenna, the transmission line, and the device is attached. To the importance of an antenna that is both resonant and matched consider that an antenna with a VSWR of 1.5 will effectively transmit approximately 95% of its power while an antenna with a VSWR of 10 will only transmit about 30%. fully appreciate DESIRED FREQUENCY to which it figure 16: Attenuation pad layout Page 10 A B C Page 11 GUIDELINES FOR ACHIEVING OPTIMUM ANTENNA PERFORMANCE 1. Proximity to objects such as a users hand or body, or metal objects will cause an antenna to detune. For this reason the antenna shaft and tip should be positioned as far away from such objects as possible. COMMON ANTENNA STYLES There are literally hundreds of antenna styles that can be successfully employed with the LC Series. Following is a brief discussion of the three styles most commonly utilized in compact RF designs. Additional antenna information can be found in Linx application notes

#00500, #00100, #00126 and #00140. Linx also offers a broad line of antennas and connectors which offer outstanding performance and cost-effectiveness. 2. Optimum performance will be obtained from a 1/4- or 1/2-wave straight whip mounted at a right angle the groundplane. In many cases this isnt desirable for practical or ergonomic reasons; thus, an alternative antenna style such as a helical, loop, patch, or base-loaded whip may be utilized. to OPTIMUM USEABLE NOT RECOMMENDED figure 17: Groundplane orientation Whip Style 3. If an internal antenna is to be used, keep it away from other metal components, particularly large items like transformers, batteries, and PCB tracks and groundplanes. In many cases, the space around the antenna is as important as the antenna itself. NUT CASE area groundplane 4. In many antenna designs, particularly 1/4-wave whips, the groundplane acts as a counterpoise, forming, in essence, a 1/2-wave dipole. For this reason adequate is essential. The groundplane can be a metal case or ground-fill areas on a figure 18: External antenna mounting circuit board. Ideally, the groundplane to be used as counterpoise should have a surface area the overall length of the 1/4-wave radiating element; however, Linx recognizes that this is impossible for most compact designs, so all Linx antennas are characterized using a 4.5 X 4.5 groundplane with the antenna centered and oriented at a 90 angle. Such an orientation is often not practical due to size and configuration constraints. In these instances a designer must make the best use of the area available to create as much groundplane in proximity to the base of the antenna as possible. In instances where the antenna is remotely located or the antenna is not in close proximity to a circuit board plane or grounded metal case, a small metal plate may be fabricated to maximize antenna performance. GROUNDPLANE

(MAY BE NEEDED) 5. Remove the antenna as far as possible from potential interference sources. There are many possible sources of internally generated interference. Switching power supplies, oscillators, even relays can also be significant sources of potential interference. Remember, the single best weapon against such problems is attention to placement and layout. Filter the modules power supply with a high-frequency bypass capacitor. Place adequate groundplane under all potential sources of noise. Shield noisy board areas whenever practical. 6. In some applications it is advantageous to place the transmitter and its antenna away from the main equipment. This avoids interference problems and allows the antenna to be oriented for optimum RF performance. Always use 50 coax such as RG-174 for the remote feed. Page 12 1/4-wave wire lengths for LC frequencies:

315Mhz=8.9"

418Mhz=6.7"

433Mhz=6.5"

Helical Style Loop Style A whip-style monopole antenna provides outstanding overall performance and stability. A low-cost whip can be easily fabricated from wire or rod, but most product designers opt for the improved performance and cosmetic appeal of a professionally made model. To meet this need, Linx offers a wide variety of straight and reduced-height whip-style antennas in permanent and connectorized mounting styles. The wavelength of the operational frequency determines an antenna's overall length. Since a full wavelength is often quite long, a partial 1/4-

wave antenna is normally employed. Its size and natural radiation resistance make it well matched to Linx modules. The proper length for a 1/4-wave antenna can be easily found using the formula below. It is also possible to reduce the overall height of the antenna by using a helical winding. This decreases the antenna's bandwidth but is an excellent way to minimize the antenna's physical size for compact applications. L =

234 FMHz Where:

L=length in feet of quarter-wave length F=operating frequency in megahertz A helical antenna is precisely formed from wire or rod. A helical antenna is a good choice for low-cost products requiring average range-

performance and internal concealment. A helical can detune badly in proximity to other objects and its bandwidth is quite narrow so care must be exercised in layout and placement. A loop- or trace-style antenna is normally printed directly on a product's PCB. This makes it the most cost-effective of antenna styles. There are a variety of shapes and layout styles which can be utilized. The element can be made self-resonant or externally resonated with discrete components. Despite its cost advantages, PCB antenna styles are generally inefficient and useful only for short-range applications. Loop-

style antennas are also very sensitive to changes in layout or substrate dielectric which can introduce consistency issues into the production process. In addition, printed styles initially are difficult to engineer, requiring the use of expensive equipment including a network analyzer. An improperly designed loop will have a high SWR at the desired frequency which can introduce substantial instability in the RF stages. Linx offers a low-cost planar antenna called the SPLATCH which is an excellent alternative to the sometimes problematic PCB trace style. This tiny antenna mounts directly to a product's PCB and requires no testing or tuning. Its design is stable even in compact applications and it provides excellent performance in light of its compact size. Page 13 LEGAL CONSIDERATIONS NOTE: LC Series Modules are designed as component devices which require external components to function. The modules are intended to allow for full Part 15 compliance; however, they are not approved by the FCC or any other agency worldwide. The purchaser understands that approvals may be required prior to the sale or operation of the device, and agrees to utilize the component in keeping with all laws governing its operation in the country of operation. When working with RF, a clear distinction must be made between what is technically possible and what is legally acceptable in the country where operation is intended. Many manufacturers have avoided incorporating RF into their products as a result of uncertainty and even fear of the approval and certification process. Here at Linx our desire is not only to expedite the design process, but also to assist you in achieving a clear idea of what is involved in obtaining the necessary approvals to market your completed product legally. In the United States the approval process is actually quite straightforward. The regulations governing RF devices and the enforcement of them are the responsibility of the Federal Communications Commission. The regulations are contained in the Code of Federal Regulations (CFR), Title 47. Title 47 is made up of numerous volumes; however, all regulations applicable to this module are contained in volume 0-19. It is strongly recommended that a copy be obtained from the Government Printing Office in Washington, or from your local government book store. Excerpts of applicable sections are included with Linx evaluation kits or may be obtained from the Linx Technologies web site (www.linxtechnologies.com). In brief, these rules require that any device which intentionally radiates RF energy be approved, that is, tested, for compliance and issued a unique identification number. This is a relatively painless process. Linx offers full EMC pre-compliance testing in our HP/Emco-equipped test center. Final compliance testing is then performed by one of the many independent testing laboratories across the country. Many labs can also provide other certifications the product may require at the same time, such as UL, CLASS A/B, etc. Once your completed product has passed, you will be issued an ID number which is then clearly placed on each product manufactured. Questions regarding interpretations of the Part 2 and Part 15 rules or measurement procedures used to test intentional radiators, such as the LC modules, for compliance with the Part 15 technical standards, should be addressed to:

Federal Communications Commission Equipment Authorization Division Customer Service Branch, MS 1300F2 7435 Oakland Mills Road Columbia, MD 21046 Tel: (301) 725-1585 / Fax: (301) 344-2050 E-Mail: labinfo@fcc.gov International approvals are slightly more complex, although many modules are designed to allow all international standards to be met. If you are considering the export of your product abroad, you should contact Linx Technologies to determine the specific suitability of the module to your application. All Linx modules are designed with the approval process in mind and thus much of the frustration that is typically experienced with a discrete design is eliminated. Approval is still dependent on many factors such as the choice of antennas, correct use of the frequency selected, and physical packaging. While some extra cost and design effort are required to address these issues, the additional usefulness and profitability added to a product by RF makes the effort more than worthwhile. to SURVIVING AN RF IMPLEMENTATION Adding an RF stage brings an exciting new dimension to any product. It also means that additional effort and commitment will be needed to bring the product successfully to market. By utilizing premade RF modules, such as the LC series, the design and approval process will be greatly simplified. It is still important, however, to have an objective view of the steps necessary insure a successful RF integration. Since the capabilities of each customer vary widely it is difficult to recommend one particular design path, but most projects follow steps similar to those shown at the right. In reviewing this sample design path you may notice that Linx offers a variety of services, such as antenna design, and FCC prequalification, that are unusual for a high-volume component manufacturer. These services, along with an exceptional level of technical support, are offered because we recognize that RF is a complex science requiring the highest caliber of products and support. Wireless Made Simple is more than just a motto, its our commitment. By choosing Linx as your RF partner and taking advantage of the resources we offer, you will not only survive implementing RF, you may even find the process enjoyable. DECISION TO UTILIZE RF IS MADE RESEARCH RF OPTIONS ORDER EVALUATION KIT(S) TEST MODULE(S) WITH BASIC HOOKUP LINX MODULE IS CHOSEN INTERFACE TO CHOSEN CIRCUIT AND DEBUG CONSULT LINX REGARDING ANTENNA OPTIONS AND DESIGN LAY OUT BOARD SEND PRODUCTION-READY FOR EMC PRESCREENING PROTOTYPE TO LINX OPTIMIZE USING RF SUMMARY GENERATED BY LINX SEND TO PART 15 TEST FACILITY RECEIVE FCC ID #

COMMENCE SELLING PRODUCT TYPICAL STEPS FOR IMPLEMENTING RF HELPFUL APPLICATION NOTES FROM LINX It is not the intention of this manual to address in depth many of the issues that should be considered to ensure that the modules function correctly and deliver the maximum possible performance. As you proceed with your design you may wish to obtain one or more of the following application notes, which address in depth key areas of RF design and application of Linx products. NOTE # LINX APPLICATION NOTE TITLE 00232 00500 00130 00125 00100 00110 00140 General considerations for sending data with the LC Series Antennas: Design, Application, Performance Modulation techniques for low-cost RF data links Considerations for operation in the 260 Mhz to 470 Mhz band RF 101: Information for the RF challenged Understanding the performance specifications of receivers The FCC Road: Part 15 from concept to approval 00150 Use and design of T-Attenuation Pads Page 14 Page 15 U.S. CORPORATE HEADQUARTERS:

LINX TECHNOLOGIES, INC. 575 S.E. ASHLEY PLACE GRANTS PASS, OR 97526 Phone: (541) 471-6256 FAX: (541) 471-6251 http://www.linxtechnologies.com Disclaimer Linx Technologies is continually striving to improve the quality and function of its products; for this reason, we reserve the right to make changes without notice. The information contained in this Data Sheet is believed to be accurate as of the time of publication. Specifications are based on representative lot samples. Values may vary from lot to lot and are not guaranteed. Linx Technologies makes no guarantee, warranty, or representation regarding the suitability of any product for use in a specific application. None of these devices is intended for use in applications of a critical nature where the safety of life or property is at risk. The user assumes full liability for the use of product in such applications. Under no conditions will Linx Technologies be responsible for losses arising from the use or failure of the device in any application, other than the repair, replacement, or refund limited to the original product purchase price. Some devices described in this publication are patented. Under no circumstances shall any user be conveyed any license or right to the use or ownership of these patents. Page 16 1999 by Linx Technologies, Inc. The stylized Linx logo, Linx, and Wireless Made Simple are the trademarks of Linx Technologies, Inc. Printed in U.S.A.

Wireless Rain-Clik Rain Sensors

. . . Wireless Rain-Clik The First Reliable Wireless Rain Sensor I If the thought of running wires from a controller has kept you from adding rain sensors to your systems, now theres a hassle-free alternative. The Hunter Wireless Rain-Clik attaches quickly and easily and delivers a dependable way to ensure that your landscape isnt getting water when it doesnt need it. Simply install the receiver unit next to your irrigation controller, then install the transmitter anywhere that the device can receive representative rainfall. No ladders needed to attach to a high outcropping on a building, no messy wires to hide out of view. What could be more simple? What also sets a Hunter Rain-Clik apart are features no other rain-sensing device offers. The unique Quick Response feature allows the product to shut off immediately when it starts to rain. And, unlike its competition, Hunters sophis-

ticated sensing mechanism cannot be fouled by debris, giving the Wireless Rain-Clik the most highly accurate operation. FEATURES & BENEFITS

. . Hassle-free, Wire-free Easy Installation

. Simple to add on to a new or existing installation

. . Hunters Unique Quick Response Feature

. No need for water to accumulate for shutoff

. . Modular Mounting Options

. Variety of choices depending on the job site; gutter or wall mounts

. . Set a Maximum Dry-Out Period

. Adjust the irrigation re-start to account for varying amounts of rain

. . Operates up to 300' from the Receiver Unit

. Typical wired system limitations vanish

. . Maintenance-free Patented Sensing Mechanism

. No callbacks just set it and forget it

. . Built-in Bypass Switch on Receiver Panel

. Adds exibility to the system

. . Retro t with Ease

. Installs on any system in minutes, no stringing of wiring

. Models Wireless Rain-Clik Dimensions 3.25" diameter x 4" high or normally open Operating Speci cations

Wiring: normally closed

Time to turn off irrigation system: 2-5 minutes for the Quick Response feature

Time to reset the Quick Response unit: 4 hours maximum under dry sunny conditions

Time to reset: 3 days maximum under dry sunny conditions for the total rainfall compensation unit

Operating temperature:

32F -130F (0C - 54C)

Vent ring allows for adjustment of reset delay

UV colorfast and stable

UL listed, FCC/DOC approved, Australian Compliance, CUL

(CSA)

Rain sensor transmitting range:

up to 300 ft. line of sight Electrical Speci cations

Receiver Power: 22-28 VAC/

VDC, 100 mA (from timer transformer)

Receiver includes built-in bypass switch, no extra switch required

Works with all standard controllers P R O D U C T E X P L A N A T I O N EXAMPLE: WIRELESS RAIN-CLIK MODEL WIRELESS RAIN-CLIK Its as easy as 1-2-3: Install bracket in easy to access location like a fence;

Snap sensor in place; test system. No wires to string. Installs in minutes!

A Variety of Mounting Options Whether you offer a rain-sensing device as an upgrade to your installations or you already install one as a standard piece of equipment, wouldnt you like to have options on where you must install it? The usual place to install a rain-sensing device has been on a at vertical surface, such as a wall or fence. But, with the Hunter Wireless Rain-Clik, you can also mount the unit on a rain gutter. In addition, Hunter offers an 8" telescoping extension rod that brings the unit out from under a roof eave or other obstruction. Gutter Clip Wall Bracket 8" Telescoping Extension Rod Instant Shut Off When it Rains There are a lot of rain-sensing devices on the market today, but all of them shut off an irrigation system only when a pre-set level of accumulated water is reached. That means that even after it has started raining, a system will continue to operate, an action that can give the impression water is being wasted (not the image that a municipality wants to give its populous as they pass by parks, roadways and other city-owned lands). Only the Hunter Rain-Clik products, with their unique Quick Response feature, allow an irrigation system to shut off immediately when it starts to rain. Compact Design No ladder required to install on fences, decks, etc. Hunter Industries Incorporated The Irrigation Innovators 1940 Diamond Street San Marcos, California 92069 TEL: (1) 760-744-5240 FAX: (1) 760-744-7461 www.HunterIndustries.com 2001 Hunter Industries Incorporated P/N 700906 10/01 LIT-348.PDF