Dip Switches #4, #5 and #6 are set for either repeater or transceiver. Without following the logic, I assume this has something to do with the routing of the COS/PTT leads or, perhaps, the audio gates. Since on link returns the xmit audio to the receive lead on the same port, estalishing two simultaneous sets up a feedback path. What exactly do these switches do?
I also see a possibility of using Switch #7 to accomplish my goal, but I'd still like to know what the other switches do.