Comtech EF Data CRS-500 User Manual
Page 95
CRS-500 1:N Redundancy System
Revision 2
Cables and Connections
MN-CRS500
4–39
4.4.3.2 Different Band / Multiple Transponder Configurations
Within this same CRS-500 1:N Redundancy System, the user may employ some Traffic Modems
with 70/140 MHz as the Tx/Rx IF-Band, as well as some Traffic Modems with L-Band as the Tx/Rx
IF-Band. Examples of this configuration setup include:
• Some Traffic Modems (full duplex links) connected to 70/140MHz transponders (via [1]
CRS-282Txx and [1] CRS-282Rxx), then other Traffic Modems connected to L-Band
transponders (via [1] CRS-282TL and [1] CRS-282RL). In this configuration, the
Redundant Modem connects to all four CRS-282xx ISUs.
For CDM-625 modems, the “Tx IF” connector on some Traffic Modems can
be connected to 70/140MHz Up Converters (via [1] CRS-282Txx); the “Rx
IF” connector on that same Traffic Modem is then connected to L-Band
Down Converters (via [1] CRS-282RL).
Figure 4-15 provides an example if a 1:N configuration using CRS-282T50 and CRS-282R50 ISUs
for the CDM-625 70/140 MHz IF connections, and CRS-282TL and CRS-282RL ISUs for the CDM-
625 L-Band connections. Make IF cabling connections as follows:
First, for the Redundant Modem, using the appropriate IF cables:
• For 70/140 MHz IF Connections:
o
Connect the 70/140 MHz “Tx IF” connector on the modem to the connector labeled
“Tx REDUNDANT MODEMS | FROM MODEM 1” on the CRS-282Txx ISU, and
o
Connect the 70/140 MHz “Rx IF” connector on the modem to the connector labeled
“Rx REDUNDANT MODEMS | TO MODEM 1” on the CRS-282Rxx ISU.
• For L-Band IF Connections:
o
Connect the L-Band “Tx IF” connector on the modem to the connector labeled “Tx
REDUNDANT MODEMS | FROM MODEM 1” on the CRS-282TL ISU, and
o
Connect the L-Band “Rx IF” connector on the modem to the connector labeled “Rx
REDUNDANT MODEMS | TO MODEM 1” on the CRS-282RL ISU.
Then, for each Traffic Modem, using the appropriate IF cables:
• Typical for 70/140 MHz or L-Band IF Connections:
o
Connect the “Tx# | FROM TRAFFIC MODEM” connector (note that ‘#’ designates a
TM number from 1 to 10) on the CRS-282Txx ISU to the pertinent “Tx IF” connector
on the modem, and