Monroe Electronics R192 - Manual (Page 3)

Operation
Each of the R192 detection circuits monitor the loss of composite sync
pulses on the primary video input. It will automatically switch to the secondary
video input upon loss of sync pulses. It will remain in this state until the pri-
mary video returns, causing the R192 section to switch back to the primary
video input.
When a switch section loses primary video and switches to the secondary,
the red led panel indicator, for that sensor on the front of the R192, lights up.
The green led indicates power is being supplied to the unit.
Each of the ten (10) detector/switch sections in the R192 are independent
units.
The Ex AC connection provides a short to ground whenever the switch is in
the SECONDARY input position.
The SAP 1 and SAP 2 allow SAP switching for the user, if desired.
SAP 1 is the primary input, and SAP 2 is the secondary input.