No way you get me to put a five band 20-10 antenna in between 40 & 80
antennas spaced only 12 feet.
Something is bound to be detuned, either way, because the booms as
well will be close to something that's resonant or acts like
director/reflector to 14/18/21/24/28 MHz.
The three element KLM will suck out 15 meters if the booms are
parallel.
F12 knows where to put forty on this antenna, behind the 18 MHz
reflector. Not up, not down, but behind on the same boom. Their own 40
"N" element antennas will mess up the 18 MHz if insufficiently
separated above or below. The N element has an 18 MHz secondary
resonance. That's why they stack well with traditional tribanders.
Most other 40 meter antennas have a secondary resonance near 21 MHz.
You need another plan.
73, Guy.
----- Original Message -----
From: "Howard Brainen" <hb@customprocess.com>
To: "TowerTalk (E-mail)" <towertalk@contesting.com>
Sent: Wednesday, May 08, 2002 9:07 PM
Subject: [Towertalk] Force 12 XR-5 spacing with KLM 40 and 80
> I emailed Force 12 about this two weeks ago but no response. I'm
hoping
> someone here can help.
>
> What is the optimum spacing to minimize interaction in this
scenario:
>
> 40M 3 element KLM spaced 12 feet below KLM 80M rotary dipole. I
want to put
> the Force 12 XR-5 multi bander between them.
>
> Should it be closer to the 80M? If so, should I orient the 80M
antenna in
> line with the boom of the XR-5 or broadside to it?
>
> Force 12 talks about spacing with their own 40M beams, but results
must be
> different with the KLM's.
>
> If it makes any difference, the XR-5 and the 80M antenna will be on
the same
> mast and rotated separately from the 40M beam.
>
> Any ideas?
>
> Thanks....73, Howard WZ6Z
>
>
>
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