The cubical quad antenna was invented by Clarence Moore, W9LZX, to solve the
problem of
corona discharge damaging antenna elements when high power is combined with
high altitude.
If you google HCJB you can find out all about it.
On 8/23/2010 9:46 PM, Jim Thomson wrote:
> Date: Mon, 23 Aug 2010 19:41:14 -0700
> From: "Hardy Landskov"<n7rt@cox.net>
> Subject: Re: [Amps] Can I cool too much the tubes or ants?
>
> To all :
> Melting antennas is a very good sign since I am the last one to relate this
> story.
>
> Circa 1957. San Fernando Valley, CA
> W6HX, Ted Gillete builds a 20 meter amplifier for W6YMD using 2-- 4-1000D
> tubes. They run 7000VDC on the plate at 2 Amps. This causes the driven
> element to glow at the ends as neighbors knock on Bill's door to tell him
> there are invaders from outer space. Actually they worked many AP, VU,& 3B8
> that night. The antenna did not survive.
> Anyway that's what was relayed to me.....
> 73 Hardy N7RT
>
> ## That's called ...'corona' and it's an easy problem to fix. With
> corona, you
> are just stripping electrons right out of the air. A few methods that been
> used on the
> tips of DE's is to use AL corona balls. Another method is anti-vibration
> loops. Another
> method is to use insert machined solid AL cylinders in the tips... with the
> ends of the
> cylinders ground off, and rounded..sorta phallic looking. Another method is
> to grind and round off
> the sharp edges of the DE tips. HV acrylic spray...or corona dope can also be
> used on the last 6"
> of the DE tips. Plane silicone rubber rtv will also work. The idea here
> is... if you put a barrier between
> the HV points and the air... you can't strip electrons from the surrounding
> air... since the al tips
> are surrounded by corona dope/rtv/ge spray, etc. Being at high altitudes
> just makes the corona problem
> worse.
>
> ## Ted, W6HX was a nice fellow. I use to hear his station during the Nov SS
> phone contest all the
> time during the mid-late 70's. I think it was WB6OLD/6 that used to
> operate Ted's station, during the contests.
> Dunno what happened to WB6OLD/6 .
>
> later... Jim VE7RF
>
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--
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/
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