I have an Cushcraft A3 that I use for contest expeditions and I never had
SWR issues using the factory settings, whether CW or Phone. My traps all
have drain holes. Is I recall the traps all need to be installed in a
certain direction and location which I'm sure you already know. Is the
substituted one also new and for the same antenna? Perhaps you still have
trap issues and should contact the manufacture or a nearby object is
detuning it. I would not expect that you would have to tune this antenna if
it is in the clear and at least 30' high.
Subject: [TowerTalk] Needed: SWR Curves for A4S with or without 40M addon
From: John Crovelli <firstname.lastname@example.org>
Date: Sun, 23 Oct 2011 10:20:34 -0400
Hi Folks. Ran into issues trying to install an new A4S with 40M extension
a client last week.
Unfortunately the Cushcraft manual does not supply a set of SWR curves but
their spec sheet claims >500 khz bandwidth within 2:1 swr points on
I never saw this amount of bandwidth on 20 or 15 when following the supplied
dimensions and I could not for the life of me adjust the antenna to put the
center points where I wanted them (e.g. 14200, 21.200, 28.250)
Also noted the traps supplied with this new antenna DID NOT have drain
and one of them developed an intermittent internal connection when installed
(substituted an old trap and this condition went away).
So if anyone has SWR curves they can share with me, and other tuning info,
please send them along to me off list at email@example.com.
John Crovelli W2GD/P40W
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