Measuring Instrument for electromagnetic fields up to 60GHz. There's another one reaching up to 90GHz. If you can prove, that they are using 60GHz, you have actually also proven, that they induce "corona". So somebody please get such a device. Or some skilled electrical engineer build one which is less precise but at least can measure Emission from for example 57GHz to 63GHz combined. Or use a hacked 60GHz access point.

Further info about relevant frequencies that are dangerous to O2 and H2O see following vid.
https://www.bitchute.com/video/Z9nAbvS05837/