Operating instructions
Rear Panel Interfaces DMD20/DMD20 LBST Universal Satellite Modem
5-8 TM103 – Rev. 2.8
5.3.11 REMOTE (J20)
The Remote Port is a RS-485 or RS-232 Connection for remote monitor and control of the
modem. It is a 9-Pin Female “D” Connector. Refer to Table 5-5 for pinouts.
Table 5-5. Remote Port (RS-485 or RS-232) 9-Pin Female “D” Connector (J20)
Pin No. Signal Name Signal Direction
1 Transmit Data RS-485 (+) TX-485-B Output
2 Transmit Data RS-232 TXD-232 Output
3 Receive Data RS-232 RXD-232 Input
4 NC NC ---
5 Ground GND ---
6 Transmit Data RS-485 (–) TX-485-A Output
7 NC No Connection ---
8 Receive Data RS-485 (+) RX-485-B/CTS Input
9 Receive Data RS-485 (–) RX-485-A Input
When operating the remote port as RS232 using a cable pinned 1 for 1
may cause communication failures due to miss routing of standard
RS232 com port signals.
When operating the remote port as RS232, the cable used should only
have pins 2, 3 and 5 connected.
5.3.12 ETHERNET (J21)
The ETHERNET Port (J21) can be used for the Monitor & Control (M&C) Functions of the unit.
The physical interface is a standard female RJ-45 Connector.
Refer to Appendix E and F for proper setup of the TCP-IP interface and Web Browser
Setup.
5.4 DMD20 LBST Chassis Connections (Standard)
5.4.1 EXT REF (J10)
The External Reference Port is a 50-Ohm Female BNC Connector and will accept the following
frequencies: 1.0, 1.544, 2.0, 2.048, 5.0, and 10.0 MHz). Input level: -8.0 to 0 dBm.