[Lf] Loop preamps]

[Andre' Kesteloot]

Vernall wrote:

> Hi all,
>
> A further point about frame loop (magnetic) receiving performance is that
> the near field is generally smaller than for a similar dimensioned (active)
> (electric) vertical whip antenna.  If neighbourhood QRM is a nuisance, then
> a well-sited frame loop can generally outperform a well-sited active whip,
> with the difference being the near field pattern.  As others have commented,
> the pre-amp noise figure is unlikely to show up as a limitation (relative to
> QRN and QRM).
>
> I have also found considerable mutual coupling between my top-loaded
> vertical transmitting antenna (when tuned) and any LF receiving antenna I
> have tried, anywhere within my suburban section.  The near field of the
> tuned transmitting antenna goes far beyond my own boundary!  The practical
> solution is to leave the vertical floating during LF receive.
>
> 73, Bob ZL2CA