In another piece, it was necessary to adapt the microphone input for other devices specifically, KENWOOD, and thus achieve a more versatile use. As it turned out, it is shown in the following figure.
The device works according to our needs and requirements. Both pieces were examined at several races, even in extreme temperatures. Showed no problem. One thing, however, to resolve. If CQ Caller-3 connects to the same power source as the TRX, penetrates into the broadcast call interference (probably from the processor or timers). As the easiest solution turned out to be used for a separate power source, IE. older adapter 220V/12V DC approx. 300 mA and the problem disappeared. We use in our radioclub three this device according to the same design. All exhibit this problem. It is obvious that it is a design problem and the resolution would require some more time. The question remains whether it has verified the design for this purpose.