410–470 MHz Data Transceivers MDS 05-4121A01, Rev.
TABLE OF CONTENTS 1.0 INTRODUCTION ......................................................................... 7 1.1 Modem Speed versus Channel Bandwidth ...................................... 8 1.2 Frequency Coverage ........................................................................ 8 1.3 Radio Operating Modes ................................................................... 8 Single Frequency (Simplex) Operation ...............................................
Copyright Notice This Installation and Operation Guide and all software described herein are protected by copyright: 2008 GE MDS. All rights reserved. GE MDS reserves its right to correct any errors and omissions in this publication. Antenna Installation Warning RF Exposure 1. All antenna installation and servicing is to be performed by qualified technical personnel only. When servicing the antenna, or working at distances closer than those listed below, ensure the transmitter has been disabled. 2.
Manual Revision and Accuracy While every reasonable effort has been made to ensure the accuracy of this guide, product improvements may result in minor differences between the manual and the product shipped to you. If you have additional questions or need an exact specification for a product, please contact the factory using the information at the back of this guide. In addition, manual updates can be found online at www.gemds.com.
vi TRM SB Integration Guide MDS 05-4121A01, Rev.
1.0 INTRODUCTION This guide presents installation and operating instructions for the TRM SB digital radio transceiver. The radio is a compact, modular board well suited to user-designed customer integration with remote terminal units (RTUs), programmable logic controllers (PLCs), automatic banking machines, or similar equipment.
1.1 Modem Speed versus Channel Bandwidth The transceiver may be configured by the user to one-of-six arrangements dependent on the permissible values of over-the-air data baud rate (BAUD), Gaussian filtering (BT), and channel bandwidth (BW). The valid configurations are: Table 1. Permissible Data Configurations Baud (bps) Receive Bandwidth (BW) BT 19200 25.0 kHz .3 16000 25.0 kHz .3 9600 25.0kHz .5 9600 12.5 kHz .3 8000 25 kHz .5 8000 12.5 kHz .3 4800 25.0 kHz .5 4800 12.5 kHz .
NOTE: The transceiver does not support full-duplex operation (i.e., transmitting and receiving at the same time). For information on other products that provide this capability, contact your sales representative. Receive Only Operation The transceiver is available as a receive-only module. The operation is identical to the tranceiver model, except that the transmit functions are disabled. 1.
Invisible place holder io rad U T R TE O EM R io rad T R S E O T H PU M O C io rad U T R R TEN ASTIO M A ST TE O M RE Figure 2. MAS Point-to-Multipoint Network (Two remote stations shown—four or more are typically used) Point-to-Point System Where permitted, the transceiver may also be used in a point-to-point arrangement. A point-to-point system consists of just two radios—one serving as a master and the other as a remote—as shown in Figure 3.
1.5 Model Number Codes The radio model number is printed on the PC board or on the radio enclosure, and provides key information about how the radio was configured when was shipped from the factory. Contact GE MDS Technical Services if you have questions about the model number codes. MDS 05-4121A01, Rev.
2.0 INSTALLATION DESIGN The TRM SB transceiver is designed to be part of a larger electronic device or system. It must be provided with adequate and stable primary power, a complementary data interface and RF antenna system connections. An appropriate antenna is the only external device that is needed.
2.1 Mounting the Transceiver Figure 5 shows the mounting dimensions of the transceiver PC board. The board should be secured to the mounting surface using the holes provided at each corner of the assembly. (Fasteners are not supplied.) Invisible place holder .090" .090" .050" 1.695 .050" 1.555 1.110 1.835 Data Connector .775 .010 2.750 0.000 .090 .140 2.61 2.47 2.465 2.33 .140 0.000 .050 .140 Figure 5. Transceiver Mounting Dimensions 2.
Table 2 summarizes minimal recommended access requirements for field setup and servicing of the TRM SB radio transceiver. Other interface signal functions may be of use to field service personnel or as part of a diagnostic design for the whole user-defined package. Table 2. Configuration and Evaluation Signals Function Data Interface Pin Signal Type) Description Enable Configuration 11 Low = Enabled Enables terminal interaction with module. Disables payload throughput.
At remote sites, a directional Yagi (Figure 7) or corner reflector antenna is generally recommended to minimize interference to and from other users. Invisible place holder Figure 7. Typical Yagi Antenna for Remote Sites Feedlines The selection of antenna feedline is very important. Poor quality cables should be avoided as they result in power losses that may reduce the range and reliability of the radio system. Table 3 shows the losses that occur when using various lengths and types of cable at 400 MHz.
The positive (+) DC power must be provided through pins 23, 24, 25, 26, 27,and 28. The data signal and DC power current return (–) should be connected to pins 1, 7, 9, 19, 20, 21, 22, and 30. (See Figure 4 on Page 12 for details.) All power pins should be used to provide sufficient current capacity in transmit operation. Shutdown Mode (Energy Conservation) In some installations, such as at solar-powered sites, it may be necessary to keep the transceiver’s power consumption to an absolute minimum.
Invisible place holder Figure 8. Data Interface Connector (As viewed from above) Table 4. DATA INTERFACE Connector Pinouts Pin Number Input/ Output Pin Description 1 IN/OUT Ground 2 OUT RF synthesizer lock detect signal • High = locked (Radio ready for service) • Low = Out-of-lock (Radio disabled) • Raw / “unfiltered” 3 IN TX Data—Transmit Data (payload) in normal operation 4 OUT CD—Carrier Detect • Low whenever RSSI exceeds the programmed CDR threshold.
Table 4. DATA INTERFACE Connector Pinouts (Continued) Pin Number Input/ Output Pin Description 9 IN/OUT Ground (Power and signal) 10 11 Do not connect—Reserved for factory use only. IN CONFIG—Configure Radio • High puts radio in normal payload mode to receive or transmit data at the programmed rate • Low puts radio in setup mode to communicate with the processor at 38.
3.0 TRANSCEIVER CONFIGURATION AND DIAGNOSTIC COMMANDS The transceiver’s configuration and diagnostics are performed through the radio’s DATA INTERFACE connector through a “dumb” data terminal interface—either a personal computer or dedicated terminal. An EIA/RS-232 to TTL converter circuit may be required depending on your installation design. Configuration and diagnostic activities may be performed with the TRM SB removed from the user equipment or as an installed module in your design.
Table 5. Command Summary (Continued) Command Function BT [.x] Relative TX Bandwidth • Valid options are .3 and .5 • Leading zero (Ø) not permitted NOTE: Must complement BAUD and BW values. (See Table 1 on Page 8.) BW [xx.x] Channel Bandwidth • Options: 25 and 12.5 kHz NOTE: Must complement BT and BW values. (See Table 1 on Page 8.) CLK [xx] Clock Output Pin Selects which serial clock line to use for transmit operation.
Table 5. Command Summary (Continued) Command Function OWN [xxx] Owner’s Message Displays an optional owner message • Enter OWN to display current entry. • Enter OWN followed by up to 30 characters to program. KEY Transmitter Carrier Key • Test command for technicians to key the radio with a unmodulated carrier. • Use DKEY command to cease transmission NOTES: • Use only for test purposes. • No time-out timer on this function. DKEY Unkey Transmitter Test Carrier 3.
3.2 Initial Installation—Radio and Data Configuration Below are the basic steps for setting up of the transceiver once it is installed in the user’s product. In many cases, these steps alone are sufficient to complete the installation. This procedure assumes the TRM SB has been installed in your system/product and suitable connections have been provided for a terminal interface and antenna. 3. Install the antenna and antenna feedline for the station.
b. Set the receive frequency with the RX xxx.xxxxx command. Press ENTER after the command. c. After programming any parameter, PROGRAMMED OK will be displayed to indicate a successful entry. 8. Review and reprogram any other parameters as necessary to complement your system requirements. (See Table 5 on Page 19 for a list of all user commands.) 9. Optimize the antenna installation by measuring the received signal strength of the other station with which this station will be communicating.
• Proper programming of the transceiver’s operating parameters (see Section 3.0, TRANSCEIVER CONFIGURATION AND DIAGNOSTIC COMMANDS). • The correct interface between the transceiver and the connected data equipment (correct cable wiring, proper data format, timing, etc.). 5.0 TECHNICAL REFERENCE 5.1 Transceiver Specifications RADIO TYPE Synthesized, half duplex, 6.25 and 5.
Intermodulation Rejection: –70 dB minimum Selectivity: 60 dB typical at adjacent channel (EIA) Bandwidth: 12.5 kHz DATA INTERFACE Connector: AVX fine-pitch 5046 series Signaling: TTL Data Rate—Diagnostics: 38400 bps asynchronous Data Rate—Payload: 38400 bps synchronous Flow-Control: Synchronous serial with clock supplied by the radio in bursts of 8 bits (when the radio is ready) Data Latency: < 20 ms typical PRIMARY POWER Voltage: 3.3 Vdc (3.2–3.
Invisible place holder TRM SB MODULE 6–12 VDC IN 3.3 VDC IN ACTIVITY TEST ANTENNA/LOAD LEDS EIA/RS-232 I/O DB-25(F) Figure 9. Test and Evaluation PCB Assembly (With TRM SB module installed and retainers on RF connector end.) Table 6.
Table 6.
5.3 Vendors for Connectors The following are vendors of interface connectors that may be used on customer-designed interfaces or equipment connected to the TRM SB. These are not the only sources of these devices nor does this listing represent an endorsement by Microwave Data Systems. Data Interface Connector 30-Pin PCB SMT Receptacle, J100 GE MDS: 73-3463A12 AVX: 14-5046-030-630-829 30-Pin PCB SMT Plug, Mates with J100 GE MDS: 73-3463A13 AVX: 24-5046-030-600-829 Vendor: AVX Corporation Web: www.AVXcorp.
5.4 dBm-Watts-Volts Conversion Chart Table 7 is provided as a convenience for determining the equivalent wattage or voltage of an RF power expressed in dBm. Table 7. dBm-Watts-Volts Conversion—for 50 Ohm Systems MDS 05-4121A01, Rev. 02 dBm V Po dBm V Po dBm mV +53 +50 +49 +48 +47 +46 +45 +44 +43 +42 +41 +40 +39 +38 +37 +36 +35 +34 +33 +32 +31 +30 +29 +28 +27 +26 +25 +24 +23 +22 +21 +20 +19 +18 +17 +16 +15 +14 +13 +12 +11 +10 +9 +8 +7 +6 +5 +4 +3 +2 +1 200W 100W 80W 64W 50W 40W 32W 25W 20W 16W 12.
6.0 GLOSSARY OF TERMS If you are new to wireless networks, some of the terms used in this guide may be unfamiliar. The following glossary explains many of these terms and is helpful in understanding the operation of the transceiver. Antenna System Gain—A figure, normally expressed in dB, representing the power increase resulting from the use of a gain-type antenna.
Fade Margin—The greatest tolerable reduction in average received signal strength that is anticipated under most conditions. Provides an allowance for reduced signal strength due to multipath, slight antenna movement, or changing atmospheric losses. A fade margin of 20 is usually sufficient in most systems. Gaussian-Mean Shift Keying (GMSK) Modulation—A form of continuous-phase FSK, in which the phase is changed between bits to provide a constant envelope.
Remote (Station)—A radio in a network that communicates with an associated master station. Remote Terminal Unit—See RTU. RSSI—Received Signal Strength Indication. A measure, in dBm, of the strength of the signal received by a radio from an antenna. The radio must be properly calibrated for the RSSI value to be meaningful. RTU—Remote Terminal Unit. A data collection device installed at a remote radio site. SCADA—Supervisory Control And Data Acquisition.
IN CASE OF DIFFICULTY... GE MDS products are designed for long life and trouble-free operation. However, this equipment, as with all electronic equipment, may have an occasional component failure. The following information will assist you in the event that servicing becomes necessary. TECHNICAL ASSISTANCE Technical assistance for GE MDS products is available from our Technical Support Department during business hours (8:30 A.M.—6:00 P.M. Eastern Time).
GE MDS, LLC 175 Science Parkway Rochester, NY 14620 General Business: +1 585 242-9600 FAX: +1 585 242-9620 Web: www.GEmds.
