Thread: 20m FD Dipole
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Old June 27th 11, 06:01 PM posted to rec.radio.amateur.antenna
W8CCW W8CCW is offline
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First recorded activity by RadioBanter: May 2011
Posts: 9
Default 20m FD Dipole

On Mon, 27 Jun 2011 09:33:23 -0400, Mike Coslo wrote:

On 6/27/2011 12:44 AM, Sal M. Onella wrote:

I was seeking optimization and I got it. Example: My TS-870
electronic display lights up five little dots for a 1.5:1 SWR. As
installed, the new antenna gave me only three little dots -- most of
it probably right at the back of the radio in the transition to 75
ohms. I am very, very pleased with the results.


The fun part of antenna modeling, at least for me, is seeing how close
the real thing meets the design. We put up an antenna for FD, an 80
meter cut for the cw portion of the band, and hit it on the first try.

As for folks tuning up rain gutters and wire salvaged from an old
toaster, then making an antenna out of it, that's fun too, but the final
result isn't likely to be optimum.

- 73 de Mike N3LI -


I use EZNEC 5 nearly every day. It saves me time & money. I can
minimize my physical work as well. At 71 years old that is getting
more important every day. Last week I took down my Fan of dipoles and
put up a 40m half wave in series with an 80 meter half wave, fed at
33% from one end. The wire was handy and so was the room. What a waste
and in 90 degree + weather too. If I had modelled it first, I would
have done it. Hard to feed everywhere and the low activity seem to
endorse the computed patterns.

I ran an inverted Vee through EZ5 with 43 foot wires on each side and
it looked as good as anything on 40 & 80M and was easy to tune about
anywhere. The testing has supported that the 30M and up patterns are
not nearly as useful as the corresponding dipoles, but it does work
everywhere. I got the 43 foot wires by simply folding the excess from
an 80M dipole and taping them. Nothing permanent, no $ spent. I will
likely keep this for 40 & 80. Probably back to adding in a couple of
dipoles for 30 & 17 in a fan configuration while I consider my first
venture into my first Quad effort.

20-15-10 are covered with an A3S Cushcraft at 60 feet. I don't
understand it, but it works good.