Tri-Mode Data Transceiver Supporting Phase 1 Units MDS 05-4819A01, Rev.
OPERATIONAL & SAFETY NOTICES RF Exposure Concentrated energy from a directional antenna may pose a health hazard to humans. Do not allow people to come closer to the antenna than the distances listed in the table below when the transmitter is operating. More information on RF exposure can be found online at the following website: www.fcc.gov/oet/info/documents/bulletins. Antenna Gain vs.
INTRODUCTION This guide presents installation and operating instructions for the MDS LCT 450 Series wireless transceiver. The transceiver (Figure 1) is designed to operate in Railroad Distributed Power applications. It is software-configurable to provide flexible operation in a variety of applications using one hardware platform. It employs microprocessor control and Digital Signal Processing (DSP) technology to provide robust communications even under adverse conditions. Figure 1.
Invisibleplaceholder Antenna Connector (UHF) Power Connector: Tyco/AMP Electronics 172129-1 DC Power Input 13.6 Vdc +/-15% Figure 2. Antenna & DC Power Connectors Invisibleplaceholder LED Indicator Panel PWR TXD DCD RXD P2 Programming & Diagnostic (DB-9) P1 Control Interface Connect (DB-25) Figure 3. Data Interface Connectors & LED Status Panel 2 LCT 450 Installation/Operation Guide 05-4819A01, Rev.
INSTALLATION There are three main requirements for installing the transceiver as follows: • Adequate and stable primary power • An efficient and properly installed antenna system • Correct data connections between the transceiver and the data equipment. Figure 4 shows a typical station arrangement. This is followed by step-by-step procedures for installing the transceiver and making front and rear panel connections.
Installation Steps Below are the basic steps for installing the transceiver. Refer to Figure 4 as necessary when making cable connections. 1. Mount the transceiver to a stable surface using the U-shaped bracket provided. Begin by attaching the radio’s mounting bracket to the bottom of the transceiver case (if not already attached) using the four 6-32 x 1/4 inch (6 mm) screws supplied. Figure 5 shows the transceiver mounting dimensions with bracket attached.
CAUTION POSSIBLE EQUIPMENT DAMAGE Using screws longer than 1/4 inch (6 mm) to attach the bracket to the radio may damage the internal PC board. Use only the supplied screws. 2. Install the antenna and feedline for the station. The antenna used with the transceiver must be designed to operate in the radio’s frequency band, and be mounted in a location that provides a clear path to the other associated station(s). Use low loss coaxial feedline and keep the cable as short as possible. 3.
Invisibleplaceholder Transceiver To DB-9 Management Port PC Running Terminal Session Figure 6. PC Configuration Setup 2. Launch a terminal communications program, such as HyperTerminal (included with most WindowsTM systems). Data parameters are 8 data bits, no parity, and 1 stop bit (8N1). Data rate is determined by autobaud, but 1115200 bps is the preferred speed. 3. Press the ENTER key a few times (at half-second intervals) to obtain the ready “>” prompt on the screen.
Table 1.
DETAILED USER COMMANDS The commands in this section may be used in two ways. First, you can type only the command name to view the currently programmed data. Secondly, you can set or change the existing data by typing the command, followed by a space, and then the desired entry. In the list below, allowable programming variables, if any, are shown in brackets following the command name. ALARM Alarm Summary The ALARM command displays a summary of the radio's current operating condition.
AUDIO [ON/OFF] Audio Monitor/Orderwire Status Used to set or display Audio Monitor/Orderwire functionality (on or off) BOOT [1, 2, OTHER] Reboot Radio Used to reboot to selected image or current image if no image specified. CHAN [0-8, ALL] [RXFREQ xxx.xxxx] (MHz) [TXFREQ xxx.xxxx] (MHz) [PWR [5, 20, 25, 30] (Watts) [BW [12.5, 25] (kHz) Channel Mods... If only the first argument is given, then it displays the channel(s) parameters.
For CTS Key operation (see DEVICE command), the timer specifies how long to wait after asserting the CTS, before sending data out the DATA INTERFACE port. A timer value of zero means that data will be sent out the data port without imposing a key-up delay. (Other delays may be present based on selected radio operating parameters.
In DCE mode (the default setting), CTS will go high following RTS, subject to the CTS programmable delay time. If the DATAKEY command is set to ON, keying can be stimulated by the input of characters at the data port. Hardware flow control is implemented by signaling the CTS line if data arrives faster than it can be buffered and transmitted. In CTS KEY mode, the radio is assumed to be controlling another radio.
INIT Initialize EEPROM Defaults The INIT command is used to re-initialize the radio's operating parameters to the factory defaults. This may be helpful when trying to resolve configuration problems that may have resulted from the entry of one or more improper command settings. If you are unsure of which command setting may have caused the problem, this command allows you to get back to a known working state.
OWM [XXX...] Owner's Message This is a command to display or program an owner's message. To program the owner's message, type OWM then the message, followed by an ENTER keypress. To display the owner's message, type OWM, followed by an ENTER keypress. The owner's message appears on the display. OWN [XXX...] Owner's Name This is a command to display or program an owner's name. To program the owner's name, type OWN then the name, followed by ENTER. To display the owner's name, type OWN then ENTER.
PTT [0-255] Push-to-Talk Delay This command sets or displays the key-up delay in milliseconds. This timer specifies how long to wait after the radio receives a key signal, before actually keying the radio. REF [xxxxx] Reference Frequency RSSI Received Signal Strength Indicator This command continuously displays the radio's Received Signal Strength Indication (RSSI) in dBm units, until you press the Enter key. Incoming signal strengths from -50 dBm to -120 dBm can be read.
SCD [0-255] Soft-Carrier Dekey This command displays or changes the soft-carrier dekey delay in milliseconds. This timer specifies how long to wait after the removal of the keying signal before actually releasing the transmitter. A value of 0 milliseconds will unkey the transmitter immediately after the removal of the keying signal. SER Radio's Serial Number This command displays the radio's serial number as recorded at the factory.
A typical spectrum analyzer display is shown in Figure 8. The display creates a received signal strength indication (RSSI) vs. frequency plot for the frequency and surrounding signals. By analyzing the display, you can determine the presence of other signals near the transceiver's operating frequency. This information can be helpful in troubleshooting interference problems. SQUELCH [AUTO, BYPASSED] Squelch Operation Set or display analog squelch bypass.
When this happens, the radio must be commanded back to an unkeyed state before a new keying command is accepted. The default timer value is 30 seconds. VERSION Firmware Version Displays package version information for each firmware image. RADIO TESTS & TEST MODE COMMANDS The following are checks and settings that can be performed by a technician to ensure optimal performance of the radio. For most tests, it will be necessary to connect a PC to the radio as described in SOFTWARE COMMANDS on Page 5.
Over-Temperature Check If the transmitter is approaching an out-of-tolerance temperature condition, an error code is issued (see Table 3) and the PWR lamp will flash. Further operation may be inhibited. Over-temperature conditions should be investigated and resolved before further use of the radio. To read the actual internal temperature of the radio (in degrees Celsius), the TEMP command may be issued from a PC.
DKEY Unkey Transmitter This command deactivates the transmitter after it has been keyed with the KEY command. KEY TX Key This command activates the transmitter. See also the DKEY command. MODEM [xxxx] Analog/Digital Modem Selection This command selects the radio's modem characteristics. For digital operation enter MODEM xxxx, where xxxx equals the modem selection of the radio (9600 or 19200). For analog operation with an external modem, enter NONE for this parameter.
If the radio’s frequency has not been programmed at the factory, a default frequency will be programmed in the radio near the center of the frequency band. SELCHAN [0-8] Select Channel This command causes the radio to go to another channel when the radio is in MODE TEST. It causes the radio to select appropriate RX and TX frequencies, power level and bandwidth for that channel. TX [xxx.xxxx] TX Frequency This command displays the radio's transmit frequency in MHz or changes channel 0's transmit frequency.
LED Indicators The LED status indicators (Figure 7) are an important troubleshooting aid and should be checked whenever a problem is suspected. Table 2 describes the function of each status LED on the front panel of the radio. Invisibleplaceholder PWR TXD DCD RXD Figure 7. LED Indicators Table 2. LED Status Indicators LED Name PWR Description • Continuous—Power applied, no problems detected. • Rapid flash (5 times-per-second)—Alarm indication. TXD Unit is transmitting.
Checking for Alarms—STAT command To check for alarms, connect a terminal to the radio’s P2 Programming & Diagnostic port. See P2 PROGRAMMING & DIAGNOSTIC INTERFACE on Page 26 for pinout information. Enter STAT on the connected terminal. If no alarms exist, the message NO ALARMS PRESENT appears on the display. If an alarm does exist, a two-digit alarm code (00–31) is displayed and the event is identified as a Major or Minor Alarm. A brief description of the alarm is also given. Major Alarms vs.
Table 3. Event Codes (Cont’d) Event Code Event Class Description 12 Major Receiver time-out. No data received within the specified receiver time-out time. 13 Minor A Transmitter timeout was detected. The radio stayed keyed longer than the duration specified by the TOT command. 17 Minor A data parity fault has been detected on the PAYLOAD port. This usually indicates a parity setting mismatch between the radio and the customer equipment.
Invisibleplaceholder Figure 8. Internal Spectrum Analyzer Display P1 CONTROL INTERFACE Table 4 lists the pin functions on the P1 Control Interface connector. Table 4. P1 Control Interface Pin Descriptions (DB-25) Pin No. 24 Description 1 No connection (NC) 2 Audio Isolated Ground 3 No connection (NC) 4 Detected Audio 5 Channel Select 3 (see Note 1). 6 RXD+ (RS-485/422 digital). Output from radio. 7 PTT Keying signal (see Note 2) 8 RXD- (RS-485/422 digital) Output from radio.
Table 4. P1 Control Interface Pin Descriptions 11 Audio Isolated Ground 12 No connection (NC) 13 No connection (NC) 14 Channel Select 2 (See Note 1) 15 No connection (NC) 16 RS-485/422 Isolated Ground 17 TX Audio input to radio 18 Channel Select Isolated Ground 19 Channel Select 0 (Note 1) 20 No connection (NC) 21 PTT Isolated Ground 22 No connection (NC) 23 Channel Select 1 (Note 1) 24 TXD+ (RS-485/422 digital). Input to radio. 25 TXD- (RS-485/422 digital) Input to radio.
P2 PROGRAMMING & DIAGNOSTIC INTERFACE Table 4 lists the pin functions on the DB-9 DIAGNOSTIC INTERFACE connector. Table 6. Diagnostic Interface Pin Descriptions (DB-9) Pin No. Description 1 No connection (NC) 2 RX Data 3 TX Data 4 No connection (NC) 5 Signal Ground 6 No connection (NC) 7 No connection (NC) 8 No connection (NC) 9 No connection (NC) SPECIFICATIONS GENERAL Frequency Range*: Number of Channels: 450–512 MHz 8 RECEIVER Maximum Usable Sensitivity: 0.
12.5 kHz B/W: 25.0 kHz B/W: 9K30F1D, 9K30F2D, 9K30F3D 16K5F1D, 16K5F2D, 16K5F3D DATA CHARACTERISTICS (P1 Control Interface Connect) Payload Signaling Type: Connector Types: Payload Data Rate: CCITT V.23 DB-25 Female 1200 bps DATA CHARACTERISTICS (P2 Programming & Diagnostic Port) Connector Type: Signaling Standard: DB-9F RS-232 PRIMARY POWER Voltage: TX Supply Current: RX Supply Current: Power Connection: Fuse: 05-4819A01, Rev. 08 13.
28 LCT 450 Installation/Operation Guide 05-4819A01, Rev.
Installation Guide
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