Barnett Engineering B1474 Uživatelský manuál

RA DIO MO DEMB1474OP ER A TION MAN UAL April, 1998Manual Revision 4.1(for Version 2.1 Hardware)

B1474BARNETT EN GI NEERING LTD.PAGE 9FIGURE 1 MODEM TIMING USING RTS AND CTS

Soft ware Hand shak ing Using XON/XOFFBasic operation and timing using XON/XOFF software handshaking are as follows:• The send ing com puter be gins s

– checks the chan nel, if this fea ture is en abled. If the chan nel is free, it as serts its PTT topower up the ra dio’s trans mit ter. If the chan

5 SETUP PRO CE DURESThe semiconductors can be damaged by static discharge. Proper handling procedures must be followed. Do not touch any of the devi

GND (Chassis) Pin 1TXD Pin 2RXD Pin 3RTS Pin 4 (connect only if using hardware handshaking)CTS Pin 5 (connect only if using hardware handshaking)GND

Adjust R12 so that the modem waits when the channel is busy, and transmits when the channelis free. When the BUSY light is ON, the modem is waiting f

To operate full duplex, leave SW2.8 OFF. To operate half duplex, set switch SW2.8 ON. If a2 wire circuit is used, the modem will only operate half d

6 IN DI CA TORSThe LED indicators on the front case are used to indicate modem status:RUN Power is on the modem.BUSY The modem is waiting to transmit

B1474BARNETT EN GI NEERING LTD.PAGE 177 CONFIGURATIONRTS/CTS DE LAY20X 503 msec235X4LEDS OFFX LEDS ON1LED CON TROLSWITCH 1PTT DROP DE LAY200X300XXX

B1474BARNETT EN GI NEERING LTD.PAGE 18BUFFERUSE RTS/CTS CON TROLX USE BUFFER2SWITCH 3RTS ON4 WIRE CA BLEX 2 WIRE CA BLE4RTS ONEX TER NAL RTSX RTS ON

TA BLE OF CON TENTSFCC RE QUIRE MENTS ...21 IN TRO DUC TION...32 SPEC I FI CA TIONS ...53 NO TA

B1474BARNETT EN GI NEERING LTD.PAGE 19+V8INPUT VOLTAGEGROUNDTX WLTX WLTX RADIO7654391PIN SYMBOL DESCRIPTIONGND2RX RADIORX WLRX WLSQLPTTTRANSMIT OUTPU

9 BOARD LAY OUTB1474BARNETT EN GI NEERING LTD.PAGE 20

Barnett En gi neering Prod uct War rantyWARRANTY STATEMENTBarnett Engineering Ltd. warrants that all equipment supplied shall

11 AP PEN DIX A - OP ER A TION WITH A GE MARC V TRUNKING SYS TEMWhen ordered with the Option 002 trunking software, the B1474 will handle the special

B1474BARNETT EN GI NEERING LTD.PAGE 23FIGURE 2 MODEM TIMING FOR A GE MARC VTRUNKING SYSTEM USING RTS/CTS HANDSHAKING

Soft ware Hand shak ing Using XON/XOFFBasic operation and timing using XON/XOFF software handshaking in a trunking system is asfollows:• The send ing

No Hand shak ingBasic operation and timing with data buffering (no handshaking) in a trunking system is asfollows:• The send ing com puter be gins sen

FCC RE QUIRE MENTSThis equipment generates, uses, and can radiate radio frequency energy and, if not used inaccordance with the instruction manual, ma

1 IN TRO DUC TIONThe B1474 Radio Modem provides a reliable method of sending 1200 baud data signals overradio or cable facilities. Digital informati

In di ca tors Modem status condition is indicated by front panel LEDs. The LEDs may be disabled toconserve power.B1474BARNETT EN GI NEERING LTD.PAGE

2 SPEC I FI CA TIONSGEN ERALTrans mis sion Rate: 1200 Baud (Bell 202 sig naling) or V.23 if fac tory in stalledTrans mis sion For mat: 8 data bits, n

PTT Drop De lay: 0, 10, 20, 50, 75, 100 or 250 msec. Keeps trans mit ter keyed long enough to en sure squelch tail noise does n’t in ter fere with da

3 NO TA TIONThroughout this manual, abbreviations will be used. These abbreviations are explained here forclarity.CD Carrier DetectCOS Carrier Opera

4 OP ER A TIONThe B1474 operates from 12 to 30 VDC to provide an interface between two computer devicesand the communications channel. In the descri