[Lf] Ground Losses]

[Andre' Kesteloot]

Rik Strobbe wrote:

> At 10:24 19/07/00 -0700, G4CNN wrote:
> >I am interested to know how the guys with very low earth resistance have
> >measured it.
> >
> >Using a 50V AC transformer secondary, I found my earth resistance to be only
> >about 10 ohms, but at 136 kHz it appears to be quite different, much closer
> >to 100 ohms.
> 'Ground loss' is frequency dependent, the electric field penetrates deeper
> into the ground at lower frequencies the losses increase when frequency
> decreases.
> But the 'system loss' on LF (and probably VLF) is not only ground loss.
> Apart from the loss in the loading coil any object near the antenna will
> contribe to the loss. Especially trees tend to act as lossy capacitors on
> LF and can become a significant part of the system loss.
>
> 73, Rik  ON7YD