Comtech EF Data CDM-570A Installation And Operation Manual page 639

CDM-570A/570AL Satellite Modem with Optional Packet Processor
Revision 5
The CRS-170A provides L-Band redundancy, but when switching occurs, it accommodates more
than just the L-Band signals. On the Tx side, it switches the Tx L-Band signal, the 10 MHz
reference to the BUC, DC power to the BUC, and FSK signaling to the BUC. On the Rx side, it
switches the 10 MHz reference to the LNB, and DC power to the LNB. The Rx L-Band signal from
the LNB is split in a power divider to continuously drive both the online and offline demodulator.
The offline demodulator can then maintain lock so that it is ready to quickly assume online status
for receive traffic when a switchover is required.
1:1 IP Redundancy N–5 MN-CDM570A