>From: W8JITom@aol.com
To: <topband@contesting.com>
>Date: Mon, 14 Oct 1996 18:34:25 -0400
>
>Hi Eric,
>
>
>An important point is folklore has it that a loop is quieter by gender, or
>that a loop (or other antennas) can be shielded from electric fields. That is
>impossible, unless the antenna is made to not radiate or receive at all. We
>can only change the characteristics *very* near the antenna under some
>special cases.
>
Yes, they can be shielded fron electroSTATIC fields but not from
electroMAGNETIC fields. Only in the case where the noise field is NOT a
radiated field but is primarily due to an electrostatic field in the
vicinity of the antenna (rare) can the electrostatic shielding (or
balancing) be effective at reducing noise.
>
>I did (not) mean to imply disagreement with you at all. I was alluding to
>articles that draw capacitors from the antenna to earth, and speculate
>that moving a 130 foot long radial up a few feet or breaking a connection
>suddenly makes losses "go away". The coupling doesn't follow the normal
>distance vs field strength rules so close to the wire. It's a geometry
>problem, not a distance problem, until the wire and earth are far field
>relationship.
I didn't think you were taking issue with me. I wasn't trying to take
issue with you either. I just thought I need to restate things a bit
more clearly than I had originally. As you say there is a _lot_ of
folklore associated with this area.
73, Eric
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