The modification of an A3 was originally described by Steven Taber, W4ITD,
in the September, 1986 QST, Hints and Kinks section. I have a copy of that
page plus a detailed description of the modification of an A4. The
modification involves installing one of the add-ons on the director element
and the other on the reflector element. The 40 meter feed point is on the
reflector so a relay is required to open the center of the reflector for 40
A couple years ago I bought an A4 that had been modified with two 40 meter
add-on kits from someone near your QTH who was moving out of town. I
finally put it up late last year and found that it was badly mistuned on 20
and 40 meters - probably due to a bad trap. Two months later it came down
in a storm so I never had an opportunity to give it a good test. I haven't
decided whether to rebuild it yet. It was a huge antenna for my lot size
Let me know if you want copies of the articles.
Subject:[TowerTalk] A3S 40M mod
From: Tom Sneden, K6VCR" <firstname.lastname@example.org>Date: Tue, 13 May 2008 16:18:38
A while back I overheard a conversation about putting 2 of the 40 meter add
on kits on an A3S therefore improving the 40 meter performance.
I already have an A3S with a 40M add on and was just gifted another 40M add
on kit. Does anyone know anything about this modification?
73 de Tom, K6VCR
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