XTL Rear Accessory Wiring

[dham66]

This is the first time I'm wired an accessory for an XTL and I'm looking for some advice to make sure I'm not missing anything. All that needs to be connected to the rear accessory is a speaker and a handset (for the rear of a fire truck I assume). I've got part #HLN6863A and it is already wired for Ignition(25), Gound(14) and Emergency(15) are tied together, Speaker Hi(20), and Speaker Low(26) are already wired. I'm assuming all that's left is Aux PTT(16) and Aux Mic(23) to wire, but I haven't seen what the other end is. Am I missing anything?

[jackhackett]

You might also want to use Mic hang up (pin 22).

[Jim202]

This is the first time I'm wired an accessory for an XTL and I'm looking for some advice to make sure I'm not missing anything. All that needs to be connected to the rear accessory is a speaker and a handset (for the rear of a fire truck I assume). I've got part #HLN6863A and it is already wired for Ignition(25), Gound(14) and Emergency(15) are tied together, Speaker Hi(20), and Speaker Low(26) are already wired. I'm assuming all that's left is Aux PTT(16) and Aux Mic(23) to wire, but I haven't seen what the other end is. Am I missing anything?

Be advised that depending on the mic you use, there is a gain setting in the software for the radio. if you have low TX audio after you get the radio installed, you need to go into the radio configuration, then the radio wide selection and then go to the TX Audio Control Per Mode. In the center of the last window that opens, you will see the "EXTERNAL MIC" settings. I don't like to use the AGC selection that the radio defaults to. It has the tendency to bring up all the background noise. In a fire truck service, this is not a good idea with a normal high background noise to begin with.

Anyway, when you uncheck the AGC, the gain will default to zero "0" and you can go from there. If you mic audio is good, leave it alone. If it sounds low, then jack the gain up some. The gain window will allow you to go from a -12 to a +12 db of gain. The only way to know what the right setting will be is to try it. It will somewhat depend on the mic or source of audio your using. Remember there is a DC bias on the mic high line if you ever connect anything but a mic to this input.

Don't forget to write back to the radio if you make any changes to the settings.

Jim

[dham66]

You guys are fantastic. Thanks for all of the info