RANGER
model(s) wire color pin number
RCI 2900 Audio 2
RCI 2950 Ground 1
RCI 2970 N/C N/C
RCI 2980 Common 1
RCI 2990 PTT 3
  receive 4 or N/C*
* receive WIRE NECESSARY ON 2950 ONLY    
model(s) wire color pin number
AR-3300 Audio 1
AR-3500 Ground 2
  N/C N/C
  Common 2
  PTT 4
  receive N/C