Comtech CRS170A, its purpose is to continuously monitor a pair of modems in a redundant configuration, so that the unit automatically switches data and IF signals from the primary unit to the standby unit if an equipment failure or undesired traffic condition occur. This fully protects traffic paths, and the operator can have increased confidence that equipment failures will not adversely affect system availability. The CRS-170A is a passive switch that perform IF switching, and the data is passively switched within the pair of modems interconnected by a Y-cable. The net result is the same: both modems see the identical TX and RX traffic signals permitting the continual comparison of fault status.
Data Sheet: Comtech CRS 170A switch data sheet
For more information, please contact us at firstname.lastname@example.org