Specifications

DMD20/20LBST Universal Satellite Modem Rear Panel Interfaces
MN-DMD20-20LBST Revision 14 5–6
Note 2: Prompt alarms can be configured to support a summary of a) Prompt alarms, b) Prompt
and Tx Minor alarms, or c) Prompt and Tx minor and Tx Major Alarms.
Note 3: Service alarms can be configured to support a summary of a) Service alarms, b) Service
and Rx Minor alarms, or c) Service and Rx minor and Rx Major Alarms.
Note 4: Service alarms can be configured to support the RTS Carrier Alarms. Refer to Radyne
App Note 230 for addition information on utilizing this feature as Keyline Operation.
5.4.7 EXT CLK (J16)
The External Clock Port is a 75-Ohm Female BNC Connector. It allows interfacing to an external
clock source.
5.4.8 ASYNC (J17)
The Asynchronous Data Interface Port is a 9-Pin Female “D” Connector. Refer to Table 5-3 for
pinouts.
Table 5-3. ASYNC Port 9-Pin Female “D” Connector (J17)
Pin No. Signal Name Signal Direction
1 Receive Data B (RS-485) RXD_B Output
2 Receive Data A (RS-485/-232) RXD_A Output
3 Transmit Data A (RS-485/-232) TXD_A Input
4 Transmit Data B (RS-485) TXD_B Input
5 Ground GND ---
6 No Connection --- ---
7 No Connection --- ---
8 No Connection --- ---
9 No Connection --- ---
5.4.9 J18
Comtech EF Data factory use only.