Comtech EF Data CDM-570 - Manual (Page 459)

CDM-570/570L Satellite Modem with Optional IP Module Revision 12
Appendix H MN/CDM570L.IOM
H–7
H.5 Cabling With CDM-570 IF
Figure H-3 shows how to connect a pair of CDM-570 modems together with the CRS-180 70/140
MHz 1:1 Redundancy Switch. The table that is included here lists cable assemblies that may be
supplied with the CRS-180.
Quantity Part # Description
2 CA/WR9378-4 Control Cable, Universal, DB9 Male to Male, 4’
4 PL/0946-1 IF (Tx/Rx) Coax Cable, 50Ω Type ‘BNC’, 4’
Figure H-3. CDM-570 and CRS-180 Interconnect
It is essential to ensure that the control and IF connections, both Rx and Tx, are made correctly.
For example, the Tx IF from Unit ‘A’ connects to the Tx IF port ‘A’ on the CRS-180, and Unit
‘B’ connects to the Tx IF Port ‘B’, and the same for the Rx IF connections. Failure to observe this
requirement will result in system malfunction.
When connecting the Control cable between the CRS-180 and the modems,
ensure that screw locks on the ‘D’ type connectors are securely fastened. This
will prevent the accidental un-mating of the cable, particularly when a standby
unit is being removed or replaced.