So this antenna basically converts invisible EM to audible sound so you can "hear" nearby sources.

As far as location sound goes, we regularly use the UHF band (470-608MHz) and scan for open frequencies. This is shared with TV channels and other stuff, but usually we can find a section we can use. But even scans sometimes won't detect temporary or spurious noise on a channel, and sometimes noise hits many frequencies all at once.

If this antenna could gather things in that frequency range or thereabouts and attenuate outside that range, we could find sources of UHF noise that might be interfering with our mics. It isn't much use detecting a massively wide range of frequencies as it does now, since many things on a set use radio signals that don't interfere with each other.

But some camera equipment, designed to run in 2.4 and 5ghz ranges, bleeds into the lower UHF bands badly. I've suspected it with a few brands, but it'd be great to be able to confirm it in a way the camera folks also understood. If I was having trouble with dropouts, I could simply walk around the area with this and try to find the source of interference.

I guess I could use something like this and attach a wideband antenna loop to it, and go from there.