Note that many, many commercial TV/FM antennas have used this principle for
years. I see no reason why it wouldn't work fine scaled up some, but have
not seen it tried. Would be interesting to hear how it works.
73, Jerry W5KP
----- Original Message -----
From: "jljarvis" <jljarvis@abs.adelphia.net>
To: <towertalk@contesting.com>
Sent: Tuesday, March 19, 2002 2:12 PM
Subject: [Towertalk] Stacking Tilted LPDA's?
>
> Folks,
>
> I've lost track of who suggested this...but I would like
> to hear from anyone who has modelled or actually installed
> two log periodic arrays, stacked, but NOT parallel.
>
> That is, by tilting the leading edge downward, on the UPPER
> lpda, and the leading edge of the LOWER lpda UPWARD, it should be
> possible with an 18' boom lpda to have the first 10m elements
> spaced by 16', and the last 20m elements spaced by 32'.
>
> I haven't bothered to finesse the geometry, but it would appear
> possible to space and tilt such that you obtain maximum gain
> from the stack, when driven in phase.
>
> Anyone actually DONE this? W1CX relates seeing a pair of KLM
> 7-30 lpda's like this in Panama, while transiting the canal.
> For purposes of discussion, assume there will be no mechanical
> mounting issues.
>
>
> Jim Jarvis, N2EA
>
>
>
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