Gene:
I think the main consideration here would be mechanical, not electrical. In
fact, you could mount them BOTH at the same height.
I have modeled my entire antenna system on MININEC and the 40m pattern is
not effected by the 80m dipole. In practice, with only about 8 feet of
separation the 40m beam seems to retain its pattern....however....the yagi
is "loaded down" and the resonant QRG is moved down....ie. tune your Yagi
for SWR and F/B a bit higher than you want, and it will move down when the
80m dipole is installed.
BTW, I am just finishing my modeling of a 2 el 80m yagi using inductor
loaded 68' elements (it will be on a short-28' boom) and my plan is to mount
my 40m yagi on the same boom. Again, as expected modeling shows no pattern
interaction, but some electrical loading. F-12 sells a dual band 40m/80m
yagi also.
73, de steve VE6WZ
----- Original Message -----
From: "Eugene Jensen" <eugenejensen@nyc.rr.com>
To: <Towertalk@contesting.com>
Sent: Saturday, April 13, 2002 11:29 PM
Subject: [Towertalk] What antenna order is best
> Interaction between the EF-180B 80 meter rotatable dipole and EF-240 40
> meter 2 element yagi on a HDX555 55 foot crankup with 20 feet of .250
> 4130 chomemolly mast above the bearing. After looking at the pictures at
> ve6wz web site I now wonder which is the best of the two setups? I was
> planning on putting the rotatable dipole on top. And how far apart is it
> best to keep them from having interaction with one and another. Gene
> K2QWD
>
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