TNC to radio wiring

There are two radio ports on the 1278. These are located on the back left corner of the unit. They look like this...

These require a 5 pin DIN plug on the TNC side and a connection for the radio side. Here is the wiring diagram for the TNC to radio patch cable.

*Note: Transmitter audio is the audio output FROM the TNC (TO the transmitter) used to modulate the transmitter, and Received audio is audio TO the TNC (FROM the receiver) to be decoded.

Most newer rigs have a built in ACC jack with the correct pinouts, however, some 2 meter equipment and most older HF equipment will have to have interface boxes built.