Comtech EF Data CDM-710G - Manual (Page 71)

CDM-710G High-Speed Satellite Modem Revision 1
Rear Panel Connector Pinouts MN-CDM710G
4–5
P1 Notes :
1. The relays have low voltage contacts with transient suppressors across each pin
to ground. The Summary Relay combines Tx, Rx, and Unit Faults into a single
relay.
2. The maximum working voltage is 18VDC or 13VAC. The maximum current
rating is 1 Amp DC or 0.5 Amp AC.
4.4.2 P2 Remote Port Connector (RS-232/-485), DB-9M
The P2 Remote port connector is a 9-pin Type ‘D’ male interface with threaded jack
nuts. It is intended for connection to an M&C computer or terminal device, and is
user selectable for either RS-232 or RS-485.The connector pinout is as follows:
Pin # Description Direction
1 Ground -
2 RS-232 Transmit Data Out
3 RS-232 Receive Data In
4 Not Used -
5 Not Used -
6 RS-485 Receive Data B * In
7 RS-485 Receive Data A * In
8 RS-485 Transmit Data B Out
9 RS-485 Transmit Data A Out
* Use for 2-wire RS-485 operation
4.4.3 J7 External Reference Input
The Ext Ref (External Reference) input is a female BNC connector, used to supply a
master reference to the entire chassis. The clocks on the Framer Card and the
Modulator and Demodulator Synthesizers are locked to this input, when it is used.
Note that some data interfaces have an Ext-Clk input for synchronizing the data
sources. Refer to the applicable Data Interface chapter in this manual for details.