The RTU-292C is an automatic telephone interconnect unit for the connection of one telephone line with one radio channel. It offers the flexibility of several modes for manned or unmanned station operation.
When used in manual mode, first a radio-to-local handset link is established. Using the telephone handset in the RTU-292C, the operator then places a call to the distant telephone that will be patched into the radio link. When the party is on the line, the operator pushes a front panel button to complete the patch to the radio link. The operator may continue to communicate with either party using the unit’s handset, or may monitor both sides of the conversation with the speaker.
The RTU-292C has the ability to automatically answer incoming phone calls which can then be connected to the radio. There are also options that allow the RTU-292 to “answer” a call from a radio by listening for a specific number of squelch breaks. Once answered, the radio caller can be automatically connected to a pre-determined phone number, or the radio caller can use DTMF to specify a phone number to call.