Comtech EF Data DMD1050 - Manual (Page 75)

DMD1050 Satellite Modem Board Maintenance and Troubleshooting
MN-DMD1050 5–3
Revision 9
5.2.1.4 Minor Rx Alarms
Alarm Possible Cause
BUFF UNDERFLOW Shows that a Doppler Buffer underflow has occurred.
BUFF NEAR EMPTY Shows that the Doppler Buffer is about to underflow.
BUFF NEAR FULL Shows that the Doppler Buffer is about to overflow.
BUFF OVERFLOW Shows that a Doppler Buffer overflow has occurred.
RX DATA ACTIVITY Shows that there is no Rx Data activity. For the Ethernet Interface, Shows that no
Ethernet port is active (no cable is plugged in).
SAT AIS Shows that AIS has been detected in the receive satellite data stream.
IFEC LOCK Shows that the Inner Codec is not locked.
OFEC LOCK Shows that the Reed-Solomon Decoder is not locked.
INTERLEAVER Shows that the Reed-Solomon Interleaver is not synchronized.
EBNO (dB) Shows that the Eb/No is outside of limits.
IBS BER Shows that there are more than one in 1000 bits in error in IBS mode.
RX DVB FRAME LOCK Shows that the Rx Satellite Data Stream Framing is not DVB.
5.2.1.5 Common Major Alarms
Alarm Possible Cause
TERR FPGA CFG Shows an Interface Card FPGA configuration failure probably caused by a missing, or
wrong file.
CODEC FPGA CFG Shows Turbo Codec Card FPGA configuration failure probably caused by a missing, or
wrong file.
+1.5V RX SUPPLY Shows the measured voltage of the 1.5 Volt Rx power bus located inside the modem.
+1.5V TX SUPPLY Shows the measured voltage of the 1.5 Volt Tx power bus located inside the modem.
+3.3V SUPPLY Shows the measured voltage of the +3.3 Volt power bus located inside the modem.
+5V SUPPLY Shows the measured voltage of the +5 Volt power bus located inside the modem.
+12V SUPPLY Shows the measured voltage of the +12 Volt power bus located inside the modem.
+24V SUPPLY Shows the measured voltage of the +24 Volt power bus located inside the modem.
EXT CLOCK ACT Shows that the External Clock is not active.
EXT REF ACT Shows no activity on the External Reference.
EXT REF LOCK Shows that the External Reference PLL is not locked.
5.2.2 Alarm Masks
The DMD1050 performs a high degree of self-monitoring and fault isolation. The alarms for
these faults are separated into the following three categories: