[Lf] Ground systems]

[Andre' Kesteloot]

Laurie Mayhead wrote:

> Hi Tom,Grounding is the big problem at LF as I am sure you know.Radial
> systems that would be effective on 40, 80,or even 160 are impossible
> (100 X quarter wavelength makes the mind boggle)Ground penetration and
> the extent of the near field means that modest radial systems and
> short ground rods are virtually useless,and I have tried,I currently
> have about 500m of buried wire and 30  four foot rods.I recon I could
> disconnect most of this with no effect.I think that the same would
> apply to burried sheets of metal unless they were several hundred feet
> square ! Re. the water table  Fresh water is an insulator so no use.
> In the UK this winter the water table was on the surface,with no
> measurable difference to loss resistance. I live near salt water and a
> connection to the sea does help but only a little. For the
> Transatlantic tests I ran out 3 radial wires of about 150 feet to 4 ft
> rods in sea water . One helped but the others  added nothing. So use
> the biggest longest system you can find ie mains earth, water supply
> etc. but dont waste too much time with buried wires! far better to put
> more WIRE IN THE AIR.I have a theory that the top load should have as
> large a Footprint as possible.In my case the top load is 10X the
> length of the vert section.It does not need to be in a straight line
> and can zig-zag if necessesary.  Rik ON7YD has written this up in his
> "Antennas for 136kHz . see www.qsl.net/on7yd/Hpoe this some help. 73s
> Laurie.
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