The RT9080 Central Office unit consists of an RT8000 C.O. controller board mounted piggyback onto the 9080 interface board. The C.O controller board provides the regular RT8000 C.O. functions and is connected to the radio via the interface board. Radio parameters are programmable from a PC.

Functionally the unit operates like an RT8000 C.O.

Ring detected between Tip and ground causes tones A&C to be transmitted

Ring detected between Ring and ground causes tones A&B to be transmitted

Receipt of a carrier causes the unit to go off hook and transmit

Transparency is maintained for line reversals but not for CLID data