I have been seeking an intercom unit for a Cessna 172N that has four seats but only two headset jacks, and I would like my rear passengers to be able to communicate without yelling.
Aviation intercoms have external radio transmit switches, but the airplane also has its own built-in radio transmit system. How does the transmit function trigger in this type of system? Do they send a certain audio signal frequency or tone to the COM stack that tells it to transmit?
Are most intercoms universally compatible with all com stacks if they use the same plug types?