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[TowerTalk] Isotron

To: <towertalk@contesting.com>
Subject: [TowerTalk] Isotron
From: thompson@mindspring.com (David L. Thompson)
Date: Fri, 8 Feb 2002 09:42:53 -0500
The antennas were called something like "L'il Giant"  and actually made a
dipole into a small space by folding it up.  This introduces imductive
loading so the inventor had to cut and try to get the right length.  Barry
N6CSW at Electric Radio Magazine came across one recently in good shape.
The Isotron makes clever use of a tuned circuit on each band with a
combination of coil, radiator wire and top and bottom hat.

Both are very narrow in bandwidth and are better than no antenna at all.
Especially if you get them up in the air and in the clear.  A better bet
would be the MFJ Isoloop with the ability to tune it to frequency by remote
control.  I have a Bencher Butternut mini beam and it works well too.   The
problem with all such antennas (Butternut beam included) is matching it to
modern rigs.   The mini beam works well with my old Elmac AM/CW transmitter
as it has the old wide range Pi-L.  I made a dozen contacts on 29Mhz AM
(including VK2BA and FY5FC) and its down quite a bit from the KT34XA but its
1/2 the height. These old rigs had antenna matching built in although we
still tried to match 52 or 72 ohms.

Remember there is no free lunch!
73 Dave K4JRB


> From the descriptions I have read, the ISOTRON antenna is very similar
> to the antennas that Stan Byquist, W0-something, built in the 1960's up
> in North Dakota.  Can't remember the 'name' he gave his design, but, to
> me, it also looked like a small bedspring!
> Somewhere in my 'files' I have a copy of the original design data for
> Stan's antenna. ... just don't ask me to find it quickly!
> Don
> N8DE
>
> Ted Leaf wrote:
> >
> > Hi Guys,
> >
> > I was reading Feb. CQ Magazine and saw the article on the Isotron
antennas.
> > Quoting: *--near-dipole performance--*.
> >
> > Now has anyone had any experience with the Isotron, especially the 160M
> > version?  Is it any better than the proverbial *bedspring*, which is
about
> > the same size?
> >
> > TED. K6HI
> > Kona, Hawaii
> >




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