Comtech EF Data SDM-2020 - Manual (Page 67)

SDM-2020 Satellite Demodulator Revision 4
Front Panel Operation MN/SDM2020D.IOM
6–3
6.1.2 LED Indicators
The seven LEDs on the front panel indicate:
• Alarms
• Summary fault information
• General demodulator status
Refer to Table 6-2 for indicator descriptions.
Table 6-2. LED Indicator Description, Front Panel
Name LED Description
Alarms
Receive
Yellow A receive function is in an alarm condition.
Faults
Receive
Red A fault condition exists in the receive chain.
Stored Yellow A fault has been logged and stored.
The fault may or may not be active.
Status
Power On
Green Power is applied to the demodulator.
Sync Green The demodulator is synchronized to the data.
Carrier Detect Green Viterbi/TCM decoder is locked.
Test Mode Yellow Flashes when the demodulator is in a test configuration.
The test mode status can be identified in the Utility:
Utility System.
At system level, a fault simultaneously activates the demodulator fault relay, DF, a
TTL-OC fault indication, and turns on the RED Receive Fault LED. This condition is
used by redundancy switches to cause a switch-over to replace a failed unit.
An alarm condition turns on the YELLOW Receive Alarm LED and activates the
demodulator alarm relay. Alarms do not activate the fault indications described above.
For Single L-Band Input Connector Units - There is a status LED visible from the rear
panel of the demodulator. Refer to Table 6-3.
Table 6-3. Rear Panel LED Indicator Description
Name LED Description
LNB Power GREEN The LNB power is ON, when the LED is illuminated.
Note: Units with four L-Band input connectors have no LED indicator.