Jim:
Some earlier postings on this thread talked about slanted LPs in a
stack. What they meant is the two LPs would be pointed up (the bottom one)
and down (the top one) so that the front, shorter elements were closer
together than the rear, longer elements. If you looked at the array from
the side it would look like >.
You might see similar arrays on TV antennas, especially older
installations, where the top and bottom LPs are angled to a point toward the
short end, thus maintaing approximately proper spacing across the BW.
73 de
Gene Smar AD3F
----- Original Message -----
From: "jim Jarvis" <jimjarvis@optonline.net>
To: <towertalk@contesting.com>
Sent: Sunday, January 24, 2010 2:42 PM
Subject: Re: [TowerTalk] stacking logs
> OK, I vowed not to add further to this thread. I lied.
> Curiosity has the better of me.
>
> Where the logs are stacked horizontally, they would seem not
> to be ideally spaced for vertical angle pattern, over frequency.
>
> The installation on the DX eng'g website... N9IN or wherever it was...
> has the
> logs at 44, 74 and 116 feet. That's a 30' and 42' spacing between the
> pairs,
> and 72' between top and bottom. There may be some frequency dependent
> relationship in this spacing, but it isn't falling out in my feeble brain.
>
> The spacings don't work out with any of the free-space pattern spacings
> with which I'm familiar.
> Maybe modeled over ground, there's some sense there?
>
> In any case, if anyone is able to explain the concept, I'd be interested
> to hear it.
>
> N2EA
>
>
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