This question came up on the list earlier, and I replied off-list to the person who inquired. After that I was asked to post the procedure I used to disable the internal controller and connect and external controller.
Here is the procedure, but I must give credit to Gary “JR” Sutton, who is the one who assisted me with this… DISCONNECT and/or REMOVE the internal signaling unit. On CN6 of the repeater, apply a jumper to pins 2&3, 8&9, 10&11, respectively. If the external controller is wired CORRECTLY to the 15 pin accessory plug, it WILL work properly. NEVER use the internal controller with an external controller. You are asking for problems. Note: CN6 is also CN2 at the internal signaling unit – you can insert your jumpers at either location. Connect the controller to the 15-pin accessory plug on the rear of the repeater: Pin Function Use 1 Hook Switch Must be grounded for unit to transmit 2 TX Mod. input ground 3 Direct Modulation Input This is where your CTCSS and/or DCS output from your controller would go. (SUB TONE) 4 RX Discriminator output This is the raw receiver carrier, this is before squelch 5 TX Modulation input Transmit audio out of the controller 6 Speaker ground 7 Switched B+ 8 PTT 9 Speaker Input This ties to pin 12 to use internal speaker 10 De-Emphasis output Squelched RX audio DO NOT USE 11 GROUND 12 Speaker output RX audio controlled by volume control 13 COR output I believe this is an active low 14 N/C 15 N/C 73 de Mark – N9WYS
