Comtech EF Data SDM-2020, Installation And Operation Manual

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SDM-2020 Satellite Demodulator Data Interfaces
Rev.3 A–19
Single ended signals are open collector where:
V
oh
=12V max. And V
ol
=0.5V max. @ I
ol
=8 ma.
A pull-up resistor, external to the equipment, is required.
The fault signals, MF and DF, operate as follows: A fault is indicated by an “OFF”
collector (high) and OK status is indicated by an “ON” collector (low).
Table A-10. Auxiliary Connector Pinout
Pin # Signal Function Name Type Comment
1 GND Signal Ground
2 Demodulator Fault Indicator DF O Demodulator Summary Fault
Redundancy switch application
3 Send Timing ST-A O Modulator
SCT for terrestrial synchronization
4 N/C
5 Not Used
6 Modulator Fault Indicator MF O Modulator Summary Fault
Redundancy switch application
7 Carrier Detect /CD O Demodulator
8 Send Timing ST-B O Modulator
SCT for terrestrial synchronization
9 Master Clock MC-A I Demodulator
A.3.5 LVDS Interface Front Panel Menus
If the LVDS interface module is installed, the Utility Interface menu displays commands
specific to that interface. Those LVDS-specific commands are depicted in Chapter 3,
Utility Interface menu.
A.3.6 LVDS Interface Remote Commands
Refer to Appendix B for a listing of LVDS interface module remote control commands.