Uplinker, you are confusing large amounts of money with complicated work. I'm sure it would be pretty simple.........
No, I was talking about the actual technicallities of engineering what we used to call "talk through", which is actually fairly simple to achieve and would consist of a box of electronics costing a few hundreds. (I could make one for you if you want). You did not mention the FAA until just now.
I agree with your first point though; about waiting for a few seconds before transmitting on a new frequency. I have watched guys on the other side of the cockpit tread all over other people's transmissions and then get themselves in a right mess of "station calling?" "two stations" "say again" etc., and having to repeat themselves several times because they did not wait just a couple of seconds to check whether anybody was in the middle of a conversation.
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