LF: VLF

[Andy Talbot <andy.g4jnt@googlemail.com>]

...wishing I'd persued the NoV application a few years ago instead of just letting it slide into oblivion...

 

Has anyone yet tried a ground loop at 9kHz?   That was going to be my first (and probably only) antenna type, running a length of wire as far away from the house as I could get-away with and connecting it to a ground stake, then feeding this against the existing local earth.   I never got round to making measurements to see what sort of ground resistance might be expected, but that would have been a lot easier than winding 1.4H air wound chokes.

 

My house backs onto a main road, and there is a drainage ditch running behide trees and foliage running for about 70m in one direction that would have made a useful route to hide a wire in.  Might have been interesting hammering in a ground stake next to the footpath at the corner of the next road though !

Andy
www.g4jnt.com

2010/3/8 Wolfgang Büscher <dl4yhf@freenet.de>

Hi Stefan,

A VLF grabber would be very fine! If you can arrange that, it would perhaps be a motivation for the dreamers ;-)
 

Well there are two now (Markus' and Paul's) .. I will try to add a third but need to get away from the local QRM. The plan is to use an UHF FM link to the remote, battery-powered site but there are some issues to be solved - one of them is the lack of dynamic range of the FM transmitter/receiver, so I may have to add some analog bandpass filtering before the FM modulator (which would render it useless for broadband VLF signals, especially natural radio signals..).

Will keep you informed, when/where another VLF 'live spectrogram' goes online.

Cheers,
 Wolf .