Here is the system.  Make sure you get the Uniden Dect 6.0 (Digital) with the ear piece scket on it so you can hang the cordless phone on your

belt and put the ear bud in your ear and the mic hangs down from that.

The interface is built in a plastic Radio Shack box as you can see and the 9 volt battery powers it. Pull the battery out when your not using it or
you will be buying batteries... it supplies voltage to the voice coil in the base. Also when you get it hooked up you adjust your VOX for operation.

If you have too much audio out of the Uniden, you can either put a small pot (500K) in series with the audio out to the mic socket on your rig, or
cut and try values until you can put a fixed resistor in there so you dont overload your mic input.

The base is what is your connection  and on one of the pics you see a phone in the base it was there for charging it battery

John W3ZDF