Abstract: The connector system includes a radio mounted receptacle with an integral transfer switch, and a separate connector and cable for interface with external radio frequency (R.F.) circuits, and provides a method of connecting external R.F. circuits to a portable radio and for simultaneously and automatically transferring the internal radio circuits from an integral radio antenna to the receptacle. The integral transfer switch of the receptacle connector includes a movable conductive plunger retained within a conducting sleeve and adapted to slide in an insulator between a first position at which the head of the plunger engages an inturned end of the sleeve, and a second position in which the plunger engages a flexible contact connected to the radio circuit and moves it away from a contact connected to the selfcontained antenna.