RXM-900-HP-II Linx Technologies Inc, RXM-900-HP-II Datasheet

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... RF experience. FEATURES: APPLICATIONS INCLUDE: Revised 2/1/00 H IGH RF MODULE RXM-900-HP-II an antenna), making ORDERING INFORMATION P ERFORMANCE Figure 1: Physical Package PART # DESCRIPTION MDEV-900-HP-II Evaluation Kit 900 MHz TXM-900-HP-II Transmitter 900 MHz RXM-900-HP-II Receiver 900 MHz 0.35 ...

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SPECIFICATIONS ABOUT THESE MEASUREMENTS The performance parameters listed below are based on module operation at 25°C from a 5VDC supply unless otherwise noted recommended all ground pins be connected to the ground-plane. The pin marked N/C has no ...

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TYPICAL PERFORMANCE GRAPHS Figure 4: Receiver Turn-on Time Figure 6: RSSI Response Time *CAUTION* This product incorporates numerous static-sensitive components. Always wear an ESD wrist strap and observe proper ESD handling procedures when working with this device. Failure to observe ...

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HP-II RECEIVER MANUAL TIMING CONSIDERATIONS There are five major timing considerations the engineer must be aware of when designing with the HP Series-II receiver. These are shown in figure 8A below, and are labeled T through T 1 Parameter Figure ...

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PIN DESCRIPTIONS: PIN# Name RF Input/ 1 Antenna Input 2-8 Gnd 9 N/C CS0 10 CS1 11 12 CS2 PDN 13 14 RSSI Gnd 15 VCC 16 Analog Out 17 18 Data Out Figure 9: Pin functions and equivalent circuits ...

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... The user-supplied antenna is connected at pin 1 (see Figure 1). The HP-II-RXM RF port is matched to 50 ohms to support interface to commonly available antennas such as those manufactured by Linx. ...

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The first IF frequency is 34.7 MHz. This frequency is achieved by setting the synthesizer frequency to a value that is lower than the incoming RF energy from the antenna. A high-performance IF receiver strip is used to perform the ...

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The HP-II receiver should, as much as reasonably possible, be isolated from all other components on your PCB. Specifically, high-frequency circuitry such as crystal oscillators should be kept as far away as possible from the HP-II receiver. If the receiver ...

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... ESR bypass capacitors configured as shown in fig. 13. POWER UP SEQUENCE The HP-II-RXM is controlled by an on-board microprocessor. When power is applied, a start-up sequence is executed. At the end of the start-up sequence, the receiver is ready to receive data. Figure 14 shows the start-up sequence. This sequence is executed when power is applied to the VCC pin or when the PDN pin is cycled from low to high ...

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NOTE: READ THIS IF YOU ARE GOING TO PERIODICALLY POWER-DOWN RECEIVER!! A common method of reducing receiver power consumption is to turn the receiver off via the PDN pin for some time interval and wake the receiver periodically to check ...

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THE DATA OUTPUT 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 ...

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RX1 Channel Select Figure 17: Typical Application - RS-232 Interface RX1 Channel Select Figure 18: Typical Application - Remote-Control Receiver PROXIMITY OPERATION If modules are combined to form a transceiver they should be operated in half- duplex, meaning that only ...

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RSSI CIRCUIT The HP Series-II receivers are equipped with an on-board Received-Signal- Strength-Indicator (RSSI) circuit. RSSI is useful to check for channel occupation, and interference as well as signal strength determination. The RSSI circuit provides a DC voltage which is ...

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RECEIVER SENSITIVITY PERFORMANCE The sensitivity of a receiver is critical to the overall range-performance of a wireless link. Among wireless manufacturers this measurement is particularly subject to specmanship due to the variety of methods and conditions under which sensitivity can ...

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ANTENNA CONSIDERATIONS The choice of antennas is one of the most critical and often overlooked design considerations. The range, performance, and legality link is critically dependent upon the type of antenna employed. Proper design and matching of ...

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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 ...

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ANTENNA STYLES From a coat hanger to a tuned Yagi, there are literally hundreds of antenna styles and variations that can be employed. Following is a brief discussion of the styles most commonly utilized in compact RF designs. The selection ...

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A helical is a wire coil usually wound from steel, copper or Helical Style brass. This antenna is very efficient given its small size. The helical is an excellent choice for products requiring good range-performance and a concealed internal antenna ...

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ANTENNA SHARING Many times when a transmitter and receiver module combined to transceiver the designer will find it advantageous for the modules to share a single antenna. To accomplish this an antenna switch must be used to provide isolation between ...

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LEGAL CONSIDERATIONS NOTE: HP Series-II 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 ...

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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 ...

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Power Conversion Tables For 50 dBm mW -50 0.000 -45 0.000 -40 0.000 -35 0.000 -30 0.001 -25 0.003 -20 0.0l 0 -15 0.032 -10 0.100 -5 0.316 0 1.000 1 1.259 2 1.585 3 1.995 4 2.512 5 3.162 ...

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MISMATCH CONVERSION TABLE VSWR Insertion Loss (dB) 17.391 -6.87 11.610 -5.35 8.724 -4.33 6.997 -3.59 5.848 -3.02 5.030 -2.57 4.419 -2.20 3.946 -1.90 3.570 -1.65 3.010 -1.26 2.615 -0.97 2.323 -0.75 2.100 -0.58 1.925 -0.46 1.433 -0.14 1.222 -0.04 1.119 ...

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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 ...