Specifications
Operation PSM-500/500L/500LT SCPC Satellite Modem
Page 3-4 PSM-500/500L/500LT - Rev. 0.91
3.1.2.3 Front Panel LED Indicators
There are 12 LEDs on the modem front panel to indicate current status of the modem’s
operation. They are separated into three columns representing (from left to right) the Modulator
status, the Demodulator status and the Modem (Unit) status. The LED colors maintain a
consistent meaning. Green signifies that the indication is appropriate for normal operation, Yellow
means that there is a condition not proper for normal operation. Red indicates a fault condition
which will result in lost communications
When one of the Alarm lamps below is illuminated, the highest priority alarm condition is
displayed in the LCD window.
Modem LED Indicators
1. Power: Green – Indicates the modem unit is currently under power.
2. Alarm: Red – if summary fault condition exists from either Alarm A or
Alarm B.
3. Local: Green – Indicates that the unit is set to respond to the front
panel.
4. Remote: Green – Indicates that the unit is set to respond to the remote
control input.
Modulator LED Indicators
1. Transmit: Green – Indicates that the transmit output is currently active.
Green Flashing when an IF Looback test is active and the
carrier is configured to the “disabled” state.
2. Major Alarm: Red – Indicates that the transmit direction has failed, losing
traffic.
3. Minor Alarm: Yellow – Indicates a transmit warning condition exists.
4. Test Mode: Yellow Flashing – Indicates the modulator is involved in a
current test mode activity.
Demodulator LED Indicators
1. Lock: Green – Indicates receiver lock to an incoming CXR and data
including FEC sync.
2. Major Alarm: Red – Indicates that the receive direction has failed, losing
traffic.
3. Minor Alarm: Yellow – Indicates a receive warning condition exists, either an
incoming carrier with a low input level or a low E
b
/N
o
(programmable threshold), or a backward alarm received from
the far end.
4. Test Mode: Yellow Flashing – Indicates the receiver is involved in a current
test mode activity.