We use those hand radios. they have a range of a couple miles. Just put on vibrate. We even have a vibrate code. vibrate once if we see a deer, twice if its heading the other guys way, three times if weregetting down. You can make up your own codes. I really didn't like wearing those earpeices. We only bow hunt though, but just a thought. Same with cell phones, vibrate leave message and then we listen to message. No noise at all. Vibrate then text.Just using what we already have.

Good luck!