It costs less than $100 on Amazon. If you are transmitting on your dual-band ham HT, MURS, GMRS, FRS or VHF/UHF land mobile band frequency, it will detect your signal within 3 seconds.
This one does the same thing, and enables you to demodulate P25 and DMR (MotoTRBO) signals, and follow communciations on trunked radio systems.
Here is the professional-grade setup. This:
Combined with this:
That's what people use when they are serious about this sort of thing.
Any one of these tools will detect a transmitting dual-band ham HT, MURS, GMRS, FRS or VHF/UHF handheld within a thousand feet (that's over 3 football fields away) and a mobile or base station over a greater distance (up to 1 mile). They start at under $100, so everybody who is serious about this sort of thing should have the best one they can afford.
The flip side is that the Baofeng or whatever brand/model of ham or Part 90/95 HT is tagged by any one of these within three seconds, compromising you. The solution was talked about in an earlier blog post, but this is just one example of something in the realm of down-grid communications you may not have known about, and could get you killed (or worse) if things start getting sporty.
The Signal-3 Newsletter and Down-Grid Communications Workshop provide the distilled essence of 30 years experience in electronic communications under interesting circumstances. We are the best, and other classes are taught by graduates of the original (but now updated) Grid-Down/3% Communications Class.