Hunter WRCTX Wireless Rain-Clik Rain Sensors User Manual LC Trans Manual

Hunter Industries Inc Wireless Rain-Clik Rain Sensors LC Trans Manual

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TOP VIEW.360.500PINOUTSLC SERIES TRANSMITTER MODULE DATA GUIDE■Remote control ■Keyless entry■Garage / Gate openers■Lighting control■Medical monitoring / Call systems■Remote industrial monitoring■Periodic data transfer■Home / Industrial automation■Fire / Security alarms■Remote status / Position sensing■Long-range RFID■ Wire EliminationAPPLICATIONS INCLUDE:■Low Cost ■No External RF ComponentsRequired■Ultra-low Power Consumption■Compact Surface-Mount Package■Stable SAW-based Architecture■Supports Data Rates to 5,000 bps■Wide Supply Range (2.7-5.2 VDC) ■Direct Serial Interface■Low Harmonics■No Production TuningThe LC Series is ideally suited for volume usein OEM applications such as remote control,security, identification, and periodic datatransfer. Packaged in a compact SMD package,the LC transmitter utilizes a highly optimizedSAW architecture to achieve an unmatchedblend of performance, size, efficiency and cost.When paired with a matching LC seriesreceiver, a highly reliable wireless link isformed, capable of transferring serial data atdistances in excess of 300 Feet. No external RFcomponents, except an antenna, are required,making design integration straightforward, evenfor engineers lacking previous RF experience.TXM-315-LCTXM-418-LCTXM-433-LCPHYSICAL DIMENSIONSDESCRIPTION:FEATURES:Revised 12/21/01PART # DESCRIPTIONEVAL-***-LC Basic Evaluation KitMDEV-***-LC Master Development KitTXM-315-LC Transmitter 315 MHZTXM-418-LC Transmitter 418 MHZ TXM-433-LC Transmitter 433 MHZRXM-315-LC Receiver 315 MHZRXM-418-LC Receiver 418 MHZRXM-433-LC Receiver 433 MHZ*** Insert FrequencyNot covered in this manualLC Transmitters are supplied in tube packaging - 50 pcs. per tube.ORDERING INFORMATION

Page 3PERFORMANCE DATA– TXM-***-LCPage 2ParameterLCTX 418MHz Designation Min. Typical Max. Units Notes Frequency of Carrier FC417.925 418 418.075 MHz –Harmonic Emissions PH– – -40 dBc 4ParameterLCTX 315MHz Designation Min. Typical Max. Units NotesFrequency of Carrier FC314.925 315.0 315.075 MHz –Harmonic Emissions PH––-40 dBc 4ParameterLCTX 433MHz Designation Min. Typical Max. Units Notes Frequency of Carrier FC433.845 433.92 433.995 MHz –Harmonic Emissions PH––-45 dBc 4figure 1: Test/Basic application circuitABOUT THESE MEASUREMENTSThe performance parameters listedbelow are based on moduleoperation at 25°C from a 3.3Vdcsupply unless otherwise noted.Figure 1 at the right illustrates theconnections necessary for testingand operation. It is recommendedthat all ground pins be connectedto the groundplane.Absolute Maximum Ratings:Supply voltage VCC, using pin 7 -0.3 to +6 VDCOperating temperature -30°C to +70°CStorage temperature -45°C to +85°CSoldering temperature +225°C for 10 sec.Any input or output pin -0.3 to VCC *NOTE* Exceeding any of the limits of this section may lead topermanent damage of the device. Furthermore, extended operation atthese maximum ratings may reduce the life of this device.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 50Ωload.5, Ladj (pin 4) through 430Ωresistor.Notes:ParametersLCTX 433, 418, 315MHz Designation Min. Typical Max. Units Notes Operating Voltage Range VCC 2.7 –5.2 Volts –Current Continuous ICC –3.0 6.0 mA 1, 5Current Average ICA –1.5 –mA 2, 5Current In Sleep ISLP –– 1.5 µA 3Data Input Low VIL 0–0.4 Volts –Data Input High VIH 2.5 –VCC Volts –Oscillator Start-up Time TOSU –– 80 µS 4Oscillator Ring-down Time TORD ––100 nSec 4Output Power PO-4 0 +4 dBm 40-1-4-5-6-7 2.5 3.0 3.5 4.0 4.5-2-3SUPPLY VOLTAGE+1+3+2+4+5+6+7+85.0 (V)2.5 3.0 3.5 4.04.0 4.54.5 5.0 (V)(V)SUPPLY VOLTAGESUPPLY VOLTAGE1324567891011120With 430Ω resistor at Iadj (pin)With Iadj tied to groundSupply Current (mA)0-1-4-5-6-7 2.5 3.0 3.5 4.0 4.54.5-2-3SUPPLY VOLTAGESUPPLY VOLTAGE+1+1+3+3+2+4+4+5+5+6+6+7+7+8+85.0 (V)2.5 3.0 3.5 4.0 4.5 5.0 (V)SUPPLY VOLTAGE1324567891011120dBmWith 430Ω resistor at Iadj (pin)With Iadj tied to groundpgOutput Powerfigure 4: Typical Oscillator Turn-On Timefigure 2: Consumption vs. Supply VoltageTYPICAL PERFORMANCE GRAPHSfigure 5: Typical Oscillator Turn-Off Timefigure 3: Typical RF power into 50ΩDataCarrierDataCarrier

Page 7Output Isolation & Filter RF AmplifierKeyed OutputVcc SAW OscillatorData In300-5000 BPS50 Ω RF OUT(Ant.)figure 11: LC Series Transmitter Block Diagram MODULE DESCRIPTIONThe LC-TXM is a low-cost, high-performance SAW-(Surface Acoustic Wave) basedCPCA (Carrier-Present Carrier-Absent) transmitter capable of sending serial data atup to 5,000 bits/second. The LC’s compact surface-mount package integrates easilyinto existing designs and is equally friendly to prototype and volume production. TheLC’s ultralow power consumption makes it ideally suited for battery poweredproducts. When combined with a Linx LC series receiver a reliable RF link capableof transferring data over line-of-sight distances in excess of 300 feet (90M) is formed.THEORY OF OPERATIONThe LC-TXM transmits data using CPCA (Carrier-Present Carrier-Absent)modulation. This type of AM modulation is often referred to by other designationsincluding CW and OOK. This type of modulation represents a logic low ‘0’by theabsence of a carrier and a logic high ‘1’by the presence of a carrier. This modulationmethod affords numerous benefits. Three of the most important are: 1) Cost-effectiveness due to design simplicity. 2) No minimum data rate or mark/space ratiorequirement. 3) Higher output power and thus greater range in countries (such as theUS) where output power measurements are averaged over time. (Please refer toLinx application note #00130).The LC-TXM is based on a simple but highly optimized architecture which achievesa high fundamental output power with low harmonic content. This insures that mostapproval standards can be met without external filter components.The LC transmitteris exceptionally stable over time, temperature, and physical shock as a result of theprecision SAW (Surface Acoustic Wave) frequency reference. Due to the of the SAWdevice most of the output power is concentrated in a narrow bandwidth. This allowsthe receiver’s pass opening can be quite narrow, thus increasing sensitivity andreducing susceptibility to near-band interference. The quality of components andoverall architecture utilized in the LC series is unusual in a low-cost RF device and isone reason the LC transmitter is able to outperform far more expensive products.THE DATA INPUTA CMOS/TTL level data input is provided on pin 2. This pin is normally supplied witha serial bitstream input directly from a microprocessor, encoder, or UART. Duringstandby or the input of a logic low, the carrier is fully suppressed and the transmitterconsumes less than 2µA of current. During a logic high the transmitter generates acarrier to indicate to the receiver the presence of a logic 1. The applied data shouldnot exceed a rate of 5,000 bits/sec. The data input pin should always be driven witha voltage common to the supply voltage present at pin 7 (Vcc). The data pin shouldnever be allowed to exceed the supply voltage (Vcc).Page 6PIN DESCRIPTIONS:Pin 1 GROUNDConnect to quiet ground or groundplane.Pin 2 DATA INSerial data input pin. TTL and CMOS compatible.Pin 3 GROUNDConnect to quiet ground or groundplane.Pin 4 LADJ/GNDOutput power level adjustment. Connect to groundfor 3V operation. Connect to ground through 430Ohm resistor for 5V operation. (see graph on page 3 and page 10)Pin 5 RF OUTConnect to 50Ωmatched antenna.Pin 6 GROUNDConnect to quiet ground or groundplane.Pin 7 POSITIVE SUPPLY (Vcc 2.7-6 VDC)The supply must be clean (<20 mV pp), stable andfree of high-frequency noise. A supply filter isrecommended unless the module is operated from its own regulated supply orbattery.Pin 8 GROUNDConnect to quiet ground or groundplane.POWER SUPPLY REQUIREMENTSThe transmitter module requires a clean, well-regulated power source. While it is preferable to powerthe unit from a battery, the unit can also be operatedfrom a power supply as long as noise and ‘hash’arekept to less than 20 mV. A 10Ωresistor in series withthe supply followed by a 10µF tantalum capacitor fromVcc to ground as shown at the right will help in caseswhere the quality of supply power is poor. figure 10: Supply FilterPHYSICAL PACKAGINGThe transmitter is packaged as a hybrid SMD module with eight pads spaced0.100" apart on center. The SMD package is equipped with castellations whichallow for side introduction of solder. This simplifies prototyping or hand assemblywhile maintaining compatibility with automated pick-and-place equipment.Modules are available in tube or tape-and-reel packaging (see page 1 forordering information).TOP VIEW.150 Max..505.365.100 (Typ.).103.103.060 x .060Typ.SIDE VIEWBOTTOM VIEW.042.2901 2 3 4 8 7 6 5 figure 9: LC -TXM Physical Package10R

Page 9BOARD LAYOUT CONSIDERATIONSIf you are at all familiar with RF devices youmay be concerned about specialized boardlayout requirements. Fortunately, becauseof the care taken by Linx in designing theLC series, integration is verystraightforward. This ease of applicationresults from the advanced multi-layerconstruction of the module. By adhering tothe following layout principles andobserving a few basic design rules, you canenjoy a straightforward path to RF success.1. A groundplane should be placed underthe module as shown. It will generally beplaced on the bottom layer. The amountof overall plane is also critical for thecorrect function of many antenna styles and is covered in the next section.2. Observe appropriate layout practice between the module and its antenna. Asimple trace may suffice for runs of less than .25" but longer distances should becovered using 50Ωcoax or a 50Ωmicrostrip transmission line. In order tominimize loss and detuning, a microstrip transmission line is commonly utilized.The term microstrip refers to a PCB trace running over a groundplane, the widthof which has been calculated to serve as a 50Ωtransmission line.This effectivelyremoves the trace as a source of detuning. The correct trace width can be easilycalculated using the information below.The width is based on the desiredcharacteristic impedance, the thickness of the PCB, and its dielectric constant.GROUNDPLANEON BOTTOM LAYERfigure 13: Example of proper groundplane EffectiveDielectric Width/Height Dielectric CharacteristicConstant (W/d) Constant Impedance4.8 1.8 3.59 50.04 2 3.07 51.02.55 3 2.12 48.0figure 14: Microstrip formulas (Er = Dielectric constant of pc board material)Page 8Notes:1) DIP Switch used to set ID code. A 3-position switch was chosen for this example but all or none of theaddress bits may be used. Settings of the Receiver and Transmitter must match for signal to be recognized.figure 12: Basic Remote Control Transmitter CircuitTRANSMITTING DATAOnce a reliable RF link has been established, the challenge becomes how toeffectively transfer data across it. While a properly designed RF link provides reliabledata transfer under most conditions, there are still distinct differences from a wiredlink that must be addressed. Since the LC modules do not incorporate internalcoding/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 possiblefrom those that are legally allowable in the country of intended operation. You maywish to review application notes #00125 and #00140 along with Part 15 Sec. 231 forfurther details on acceptable transmission content.Another consideration is that of data structure or protocol. If you are not familiar withthe sending serial data in a wireless environment read Linx application note #00232(Considerations for sending data with the LC series). This application note detailsimportant issues such as the effect of start-up times, pulse stretching and shorteningand 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 switchclosures, consider using an encoder and decoder IC set available from a wide rangeof manufacturers including: Microchip (Keeloq), Holtek, and Motorola.These IC’s takecare of all encoding, error checking, and decoding functions and generally provide anumber of data pins to which switches can be directly connected. Address bits areusually provided for security and to allow the addressing of multiple receiversindependently. Additionally, it is a simple task to interface with inexpensivemicroprocessors such as the Microchip PIC or one of many IR, remote control,DTMF, and modem IC’s.Shown below is an example of a basic remote control transmitter utilizing a encoderchip from Holtek.When a key is pressed at the transmitter, a corresponding pin at thereceiver goes high. A schematic for the receiver/decoder circuit may be found in theLC receiver guide.

Page 11ANTENNA CONSIDERATIONSThe choice of antennas is one of the most critical and often overlooked designconsiderations. The range, performance, and legality of an RF link is criticallydependent upon the type of antenna employed. Proper design and matching of anantenna is a complex task requiring sophisticated test equipment and a strongbackground in principles of RF propagation. While adequate antenna performancecan often be obtained by trial and error methods, you may also want to considerutilizing a professionally designed antenna such as those offered by Linx. Our low-cost antenna line is designed to ensure maximum performance and compliance withPart 15-attachment requirements. The purpose of the following sections is to giveyou a basic idea of some of the considerations involved in the design and selectionof antennas. For a more comprehensive discussion please review Linx applicationsnote #00500 “Antennas: Design, Application, Performance”.THE TRANSMITTER ANTENNAThe transmitter antenna allows RF energy to be efficiently radiated from the outputstage into free space. In modular designs such as the LC, a transmitter’s outputpower is often slightly higher than the legal limit. This allows a designer to utilize aninefficient antenna in order to achieve full legal power while meeting size, cost, orcosmetic objectives. For this reason a transmitter's antenna can generally be lessefficient 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 shouldbe 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, inductivereactance will be present. The indicator of resonance is the minimum point in theVSWR curve. You will see from the following example that antenna (A) is resonantat too low a frequency, indicating excessive length, while antenna (C) is resonant attoo 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 differencebetween resonance and impedance is most easily understood by considering thevalue of VSWR at its lowest point. The lowest point of VSWR indicates the antennais resonant, but the value of that low point is determined by the quality of the matchbetween the antenna, thetransmission line, and thedevice to which it isattached.To fully appreciate theimportance of an antennathat is both resonant andmatched consider that anantenna with a VSWR of1.5 will effectively transmitapproximately 95% of itspower while an antennawith a VSWR of 10 will onlytransmit about 30%.AB CDESIRED FREQUENCYPage 103. 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 designerspair the module with an inefficient antenna in order to realize cost or spacesavings. Since attenuation is often required it is generally wise to provide for itsimplementation.Two methods of attenuation are available using the LC module. First, a resistormay be placed in series with Pad 4 (LVL. ADJ.) to achieve up to a 7 dB reductionin 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 powerconsumption.CIRCUIT TYPICAL LAYOUTWITH PROVISION FOR ATTENUATIONGNDANT. OUTPADS FOR SMTRESISTORSPADS FOR SMTRESISTORS ANT.ANT.R1R1 R2GRGROUNDPLANEOUNDPLANEON LOON LOWER LAWER LAYERYERGROUNDPLANEON LOWER LAYERGRGROUND OUND GROUNDGRGROUND OUND GROUNDfigure 16: Attenuation pad layout+8+7+6+5+4+3+2+10-1-2-3-4LADJ Pin Resistor Value51 100 150 200 240 300 360 430 510 560 620 680 750 820 910 1.1KOutput Power dBm3V5Vfigure 15: Power Output vs. LADJ Pad Resistor ValueAnother method commonly used to achieve attenuation, particularly at higherlevels, is the use of a T-pad. A T-pad is a 3-resistor network that allows for variableattenuation while maintaining the quality of match to the antenna. It is usuallyprudent to allow space for the addition of a T-pad. For further details on T-padsplease refer to Linx application note #00150.

GUIDELINES FOR ACHIEVING OPTIMUM ANTENNA PERFORMANCE1. Proximity to objects such as a user’s hand or body, or metal objects will causean antenna to detune. For this reason the antenna shaft and tip should bepositioned as far away from such objects as possible.2. Optimum performance will be obtainedfrom a 1/4- or 1/2-wave straight whipmounted at a right angle to thegroundplane. In many cases this isn’tdesirable for practical or ergonomicreasons; thus, an alternative antennastyle such as a helical, loop, patch, orbase-loaded whip may be utilized.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 andgroundplanes. In many cases, the space around the antenna is as importantas the antenna itself.4. In many antenna designs, particularly1/4-wave whips, the groundplane actsas a counterpoise, forming, in essence,a 1/2-wave dipole. For this reasonadequate groundplane area isessential. The groundplane can be ametal case or ground-fill areas on acircuit board. Ideally, the groundplane tobe used as counterpoise should have a surface area ≥the overall length of the1/4-wave radiating element; however, Linx recognizes that this is impossible formost compact designs, so all Linx antennas are characterized using a 4.5”X4.5”groundplane with the antenna centered and oriented at a 90°angle. Suchan 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 tocreate as much groundplane in proximity to the base of the antenna aspossible. In instances where the antenna is remotely located or the antenna isnot in close proximity to a circuit board plane or grounded metal case, a smallmetal plate may be fabricated to maximize antenna performance.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 significantsources of potential interference. Remember, the single best weapon againstsuch problems is attention to placement and layout. Filter the module’s powersupply with a high-frequency bypass capacitor. Place adequate groundplaneunder all potential sources of noise. Shield noisy board areas wheneverpractical.6. In some applications it is advantageous to place the transmitter and itsantenna away from the main equipment.This avoids interference problems andallows the antenna to be oriented for optimum RF performance. Always use50Ωcoax such as RG-174 for the remote feed.Page 13Helical StyleWhip StyleLoop Style1/4-wave wire lengthsfor LC frequencies:315Mhz=8.9"418Mhz=6.7"433Mhz=6.5"Where:L=length in feet of quarter-wave length F=operating frequency in megahertzCOMMON ANTENNA STYLESThere are literally hundreds of antenna styles that can be successfully employed with theLC Series. Following is a brief discussion of the three styles most commonly utilized incompact 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 andconnectors which offer outstanding performance and cost-effectiveness.A whip-style monopole antenna provides outstanding overallperformance and stability. A low-cost whip can be easily fabricated fromwire or rod, but most product designers opt for the improvedperformance and cosmetic appeal of a professionally made model. Tomeet this need, Linx offers a wide variety of straight and reduced-heightwhip-style antennas in permanent and connectorized mounting styles.The wavelength of the operational frequency determines an antenna'soverall length. Since a full wavelength is often quite long, a partial 1/4-wave antenna is normally employed. Its size and natural radiationresistance make it well matched to Linx modules. The proper length fora 1/4-wave antenna can be easily found using the formula below. It isalso possible to reduce the overall height of the antenna by using ahelical winding. This decreases the antenna's bandwidth but is anexcellent way to minimize the antenna's physical size for compactapplications.A helical antenna is precisely formed from wire or rod. A helical antennais a good choice for low-cost products requiring average range-performance and internal concealment. A helical can detune badly inproximity to other objects and its bandwidth is quite narrow so care mustbe exercised in layout and placement.A loop- or trace-style antenna is normally printed directly on a product'sPCB. This makes it the most cost-effective of antenna styles. There area variety of shapes and layout styles which can be utilized.The elementcan be made self-resonant or externally resonated with discretecomponents. Despite its cost advantages, PCB antenna styles aregenerally inefficient and useful only for short-range applications. Loop-style antennas are also very sensitive to changes in layout or substratedielectric which can introduce consistency issues into the productionprocess. 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 desiredfrequency which can introduce substantial instability in the RF stages.Linx offers a low-cost planar antenna called the “SPLATCH”which is anexcellent alternative to the sometimes problematic PCB trace style.Thistiny antenna mounts directly to a product's PCB and requires no testingor tuning. Its design is stable even in compact applications and itprovides excellent performance in light of its compact size.L =234FMHzPage 12NUT GROUNDPLANE (MAY BE NEEDED)CASEOPTIMUMUSEABLE NOT RECOMMENDEDfigure 17: Groundplane orientationfigure 18: External antenna mounting

Page 15Page 14SURVIVING AN RF IMPLEMENTATIONAdding an RF stage brings an exciting new dimensionto any product. It also means that additional effort andcommitment will be needed to bring the productsuccessfully to market. By utilizing premade RFmodules, such as the LC series, the design andapproval process will be greatly simplified. It is stillimportant, however, to have an objective view of thesteps necessary to insure a successful RFintegration. Since the capabilities of each customervary widely it is difficult to recommend one particulardesign path, but most projects follow steps similar tothose shown at the right.In reviewing this sample design path you may noticethat Linx offers a variety of services, such as antennadesign, and FCC prequalification, that are unusual fora high-volume component manufacturer. Theseservices, along with an exceptional level of technicalsupport, are offered because we recognize that RF isa complex science requiring the highest caliber ofproducts and support. “Wireless Made Simple”ismore than just a motto, it’s our commitment. Bychoosing Linx as your RF partner and takingadvantage of the resources we offer, you will not onlysurvive implementing RF, you may even find theprocess enjoyable.DECISION TO UTILIZE RF IS MADERESEARCH RF OPTIONSLINX MODULE IS CHOSENORDER EVALUATION KIT(S)TEST MODULE(S) WITHBASIC HOOKUPINTERFACE TO CHOSEN CIRCUIT AND DEBUGCONSULT LINX REGARDINGANTENNA OPTIONS AND DESIGNLAY OUT BOARDSEND PRODUCTION-READYPROTOTYPE TO LINXFOR EMC PRESCREENINGOPTIMIZE USING RF SUMMARY GENERATED BY LINXSEND TO PART 15TEST FACILITYRECEIVE FCC ID #COMMENCE SELLING PRODUCTTYPICAL STEPS FORIMPLEMENTING RFHELPFUL APPLICATION NOTES FROM LINXIt is not the intention of this manual to address in depth many of the issues thatshould be considered to ensure that the modules function correctly and deliverthe maximum possible performance. As you proceed with your design you maywish to obtain one or more of the following application notes, which address indepth key areas of RF design and application of Linx products.00232 General considerations for sending data with the LC Series00500 Antennas: Design, Application, Performance00130 Modulation techniques for low-cost RF data links00125 Considerations for operation in the 260 Mhz to 470 Mhz band00100 RF 101: Information for the RF challenged00110 Understanding the performance specifications of receivers00140 The FCC Road: Part 15 from concept to approval00150 Use and design of T-Attenuation PadsNOTE # LINX APPLICATION NOTE TITLELEGAL CONSIDERATIONSWhen working with RF, a clear distinction must be made between what is technicallypossible and what is legally acceptable in the country where operation is intended.Many manufacturers have avoided incorporating RF into their products as a result ofuncertainty and even fear of the approval and certification process. Here at Linx ourdesire is not only to expedite the design process, but also to assist you in achievinga clear idea of what is involved in obtaining the necessary approvals to market yourcompleted product legally.In the United States the approval process is actually quite straightforward. Theregulations governing RF devices and the enforcement of them are the responsibilityof the Federal Communications Commission. The regulations are contained in theCode of Federal Regulations (CFR), Title 47. Title 47 is made up of numerousvolumes; however, all regulations applicable to this module are contained in volume0-19. It is strongly recommended that a copy be obtained from the GovernmentPrinting Office in Washington, or from your local government book store. Excerpts ofapplicable sections are included with Linx evaluation kits or may be obtained from theLinx Technologies web site (www.linxtechnologies.com). In brief, these rules requirethat any device which intentionally radiates RF energy be approved, that is, tested,for compliance and issued a unique identification number. This is a relatively painlessprocess. Linx offers full EMC pre-compliance testing in our HP/Emco-equipped testcenter. Final compliance testing is then performed by one of the many independenttesting laboratories across the country. Many labs can also provide othercertifications 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 isthen clearly placed on each product manufactured.Questions regarding interpretations of the Part 2 and Part 15 rules or measurementprocedures used to test intentional radiators, such as the LC modules, forcompliance 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.govInternational approvals are slightly more complex, although many modules aredesigned to allow all international standards to be met. If you are considering theexport of your product abroad, you should contact Linx Technologies to determinethe specific suitability of the module to your application.All Linx modules are designed with the approval process in mind and thus much ofthe frustration that is typically experienced with a discrete design is eliminated.Approval is still dependent on many factors such as the choice of antennas, correctuse of the frequency selected, and physical packaging. While some extra cost anddesign effort are required to address these issues, the additional usefulness andprofitability added to a product by RF makes the effort more than worthwhile.NOTE: LC Series Modules are designed as component devices which requireexternal components to function. The modules are intended to allow for full Part15 compliance; however, they are not approved by the FCC or any other agencyworldwide. The purchaser understands that approvals may be required prior tothe sale or operation of the device, and agrees to utilize the component in keepingwith all laws governing its operation in the country of operation.