I think 'Murphy' lives here!

[catman]

G'day all, well today I saw something that can't be explained and doesn't make any sense (at all) to me. My usual 20 m antenna, a full wave Quad loop had suddenly become very noisy over a couple of days, sounding like severe power line noise which we do experience here at times.

My loop was vertically polarised, so I thought ok that must be the reason so I switched it back to horizontal. Almost no difference! I thought about it for a while and ran a few diagnostics. Eveything tested 100 percent ok.

A little later on I put up my 20 m ground plane vertical (actually it's a pretty good antenna), back upstairs and connected it up and guess what, ZERO noise. I reconnected the loop and once again, a solid S7 noise!

Why? I haven't a clue. Can anybody offer any explanation? Regards, Felix (vk4fuq) aka catman.