Does anybody know how the R230 antenna amplifier is wired in?

There are the obvious two co-ax in and out terminals and the 12V feed, but there is also a small three pin data type socket as well which I guess is for some form of fine tuning, or could it be a switch for AM/FM?

I'd be grateful if anyone knows as I am fed up with my R129 aerial sticking half way up and have in mind to fit a 230 stub antenna in its place.

Thanks
Hal

 

The stub antenna is not for fm/am radio. The antenna you are referring to is part of the windshield on the w230.