Hi Moshe/Gabriel. Re: low cost scanners.
I've been using a Tandy handheld scanner with the supplied 8" whip antenna for going round 'look-seeing' equipment for years. The antenna has sufficiently low gain at frequencies below 100 MHz to make it useful as a localized sniffer. The scanner is a Realistic PRO-something-or-other, about 6 years old, and has an unsophisticated AGC, so is more useful than a modern hyper-performer. i.e. I can get subjective differences in amplitudes without the AGC making everything the same volume. Set the scanner off about 1 metre (near field) from the equipment, from 30MHz, with the squelch set to just suppress background at 27MHz (ISM stuff)and 100MHz (broadcast in the UK), and scan to 1GHz noting where it stops on non-music. After the first scan, go back and home in on the frequencies found, using the scanner as a sniffer. It's success at finding emissions is amazing, but alas often sends you off chasing ghosts which are really significantly lower than compliance levels. It's difficult ot calibrate an audible 'squawk'. Final compliance is done with a full antenna/spectrum analyser kit of course, the scanner is used to identify hot spots. Thats a tuppence worth. Chris Dupres Surrey, UK.
