Many thanks Markus for this neat explanation, and many thanks Edgar for asking
that question! :)
Especially that somehow twisted loops will not loose their nulls is a good
message to me. ;)
Greetings!
Dennis, Berlin, DL6NVC
-------- Original-Nachricht --------
> Datum: Sun, 23 Sep 2012 11:01:45 +0200
> Von: "Markus Vester" <[email protected]>
> An: [email protected]
> CC: [email protected]
> Betreff: Re: LF: loop - low angle signal reception
> Hi Edgar,
>
> good question. I think on LF, where the size of the antenna is much
> smaller than a wavelength, the shape of the loop does not affect the radiation
> pattern at all. This is even true if it were distorted in three dimensions,
> there is always an effective axis which defines the direction of the two
> opposite nulls. Also the height above ground (or below it in the case of an
> earth antenna) makes little difference.
>
> Induced voltage is proportional to area, so the 2x2 should produce
> slightly more signal than the 1x3. On the other hand, depending on local
> environment, B may be better than A in terms of ground losses and local QRM
> pickup.
>
>
> Best wishes,
> Markus
>
>
> From: Edgar J Twining
> Sent: Sunday, September 23, 2012 5:32 AM
> To: [email protected]
> Subject: LF: loop - low angle signal reception
>
>
> Hi,
> The rectangles in the image are ment to represent loop receiving
> antennas.
>
> The numbers represent the length of the sides. ie there have the same
> perimeter.
>
>
> Does making the rectangle taller provide better low angle signal
> reception?
>
> Regards Edgar
> Moonah, Tasmania.
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