Product specifications

CRS-180 70/140 MHz IF 1:1 Redundancy Switch MN/CRS180.IOM
Cables and Connections Revision 11
5–45
5.7 Cabling to the CDM-700
1) For information on configuring the CRS-180 70/140 MHz IF 1:1 Redundancy
Switch with the CDM-700 Satellite Modems for 1:1 operation, see:
• Chapter 4. MODEM
AND SWITCH CONFIGURATION
• CDM-700 Satellite Modem Installation and Operation Manual
(CEFD P/N MN/CDM700.IOM)
2) For information on the cables and cable assemblies specified in this section, see
Appendix A. CABLE DRAWINGS
5.7.1 CRS-180  CDM-700 Control and IF Interface Connections Using
Cabling Kit KT/12554
You must order terrestrial data interface components/kits separately. See Sect.
5.7.2 for more information.
You must use the Comtech EF Data KT/12554 CRS-180 70/140 MHz IF 1:1 Redundancy Kit for
your control and IF connections. Figure 5-39 shows these Switch-to-Modem control and IF
interface connections.
Figure 5-39 NOTES:
1) Use of the XF/BNC-MF-50-75 transformers (Item 2) is required on the ‘J7 | Rx’
and ‘J8 | Tx connectors, located on the antenna side of the switch, when you
supply a 75Ω Rx/Tx connection.
2) Use of the XF/BNC-MF-50-75 transformers (Item 2) on the Rx A and Rx B ports,
located on the modem side of the switch, is dependent on the CDM-700’s
factory configuration for 50
Ω
or 75
Ω
Rx operability. If the modems in use are
configured as 50
Ω
Rx units, the transformers will not be used on the Rx side and
the 50
Ω
cable (Item 4) will be used in place of the 75
Ω
cable (Item 3).
3) To provide User access to modem “Fault Summary Relay,” Control ‘Y’ Cable
CA/WR13011-4, sold separately, is available for use in place of the
CA/WR12135-1 cable.
4) Control Cable CA/WR12135-1 will mute the Offline Modem’s Tx IF. If this is not
desired, then an alternate cable, Control Cable CA-0000187, sold separately, is
available for use in place of the CA/WR12135-1 cable.