Comtech EF Data CRS-170A - Manual (Page 35)

CRS-170A L-Band 1:1 Redundancy Switch MN/CRS170A.IOM
Introduction Revision 13
1–15
Figure 1-9. CDM-570L/AL 1:1 IP Redundancy Router Mode – Switchover (‘B’
Online)
1.3.3 CRS-170A Operation with CDM-600L (CLM-9600L) and SDM-300L3
Modems
The CDM-600L (CLM-9600L) and SDM-300L3 modems do not have built-in switching capability for
the terrestrial data side of the link:
• For the CDM-600L (CLM-9600L), 1:1 redundancy requires both a CRS-150 switch to act as
controller and terrestrial data switch and a CRS-170A to perform the L-Band switching. The
CRS-170A is required because the CRS-150 RF switching is limited to the L-Band band, and will
not handle the high current BUC power supply multiplexed onto the transmit coaxial cable.
• Similarly, the SDM-300L3 requires an SMS-301 switch together with the CRS-170A.
In both cases, the CRS-170A is controlled by the supporting data switch, and places the ‘A’ or ‘B’
modem RF Online to match the data switch state. The CDM-600L (CLM-9600L) modems supply