Comtech EF Data CDM-570A - Manual (Page 146)

CDM-570A/570AL Satellite Modem with Optional Packet Processor MN-CDM570A
Front Panel Operation Revision 2
6–42
6.3.3.1.1 (MONITOR: Live Alarms) Unit
Unit Fault: -12 Volt PSU
is Under-Voltage (ENT)
This screen displays Unit Faults. If none are present, it displays ‘ None’. Press ENTER to return to
the previous menu.
6.3.3.1.2 (MONITOR: Live Alarms) Receive (Receive Traffic Status)
Rx Traffic: AGC Alarm -
Reduce Input level (ENT)
This screen displays Receive Traffic Faults. If none are present, it displays ‘ None’. Press ENTER
to return to the previous menu.
6.3.3.1.3 (MONITOR: Live Alarms) Transmit (Transmit Traffic Status)
Tx Traffic: No Tx Clock
from Terrestrial (ENT)
This screen displays Transmit Traffic Faults. If none are present, it displays ‘ None’. Press ENTER
to return to the previous menu.
6.3.3.2 MONITOR: Rx
EbNo>16.0dB BER=0.0E-9
ΔF=0.0k Buf=50 RSL=-42
If the demodulator is locked, information displays as follows:
Parameter Description
EbNo=
This shows the value of E
b
/N
0
calculated by the demodulator. The value referred to here is the
energy per information bit ( E
b
i), divided by the noise spectral density (N
0
).
BER= This shows an estimate of the corrected BER.
∆F= This shows the frequency offset of the received carrier, in kHz, in steps of 100 Hz.
Buf=
(Buffer fill state) This shows the fill state, in percent, of the receive Buffer. After a reset, it will read 50.
A value below 50 indicates that the buffer is emptying, and above 50 indicates that it is filling.
RSL=
(Receive Signal Level) This shows the value, in dBm, of the desired carrier’s input power as seen by
the demodulator. If the signal level is below the AGC range of the demod, this displays RSL <-99.
Otherwise, if the demodulator is not locked, the message ‘Demod: Not Locked’ displays,
but the screen continues to display the receive signal level, as this example shows: