If you mean RF radio, you can take the headphone out portion and
plug it straight into the
desk. If you mean something more like comm/clearcom/
RTS, then you'll need to either get a dry feed (usually the basestation will have an "Audio out" which can be plugged into the
desk). Otherwise, you will need to strip the DC
voltage from the comm
line before going into the
desk. There are schematics online for doing this with some pin swapping and a
transformer, but some companies also make an XLR-barrel type all-in-one solution.
I'm still unsure if by A2 you mean you're mixing (monitors?) or like a
stage/
backline tech with a
IEM mix? If you're at the
console, you can set up a specific mix bus for yourself. I generally take a loop out of the
monitor channels and go back into a standard input, then route that to a bus, so I can also then route things like comm or other talkback mics into that bus. Just make sure you don't solo the "
cue" input
channel. There are a few different ways to do this, entirely up to you on how you like your workflow.
If you're not the one behind the board, you might be able to ask nicely and see if they can spare a
channel for the radio/comm input, and maybe other people on the crew would be interested in being able to hear it through their IEMs as well if there are more techs with
iem packs.