I recently purchased used, from a pile of aluminum antenna parts, a Cushcraft
A4S I believe it to be as it has the extra 10 meter element. This antenna also
has the 30/40 meter add on with the heavy duty center insulator and was set up
with the spider capacitative attachments for 40 meters. Well I was just
interested in the 30 meter driven element to be used as a dipole below my
current A3S beam on my tower. I put the driven element on my deck about 8 feet
off the ground and resonated all bands where I wanted them. It checked out
fine. This required pulling off the capacitative hat and eliminating the end
rods for 30 meters.
I then mounted the antenna about 20 feet in the air on the side of my tower to
see how it would work before final installation. The 30 meter band now
resonated about 9.9 MHz instead of up into 10 MHz. I surmised that due to the
rain gutter that was near one end of the antenna. I adjusted the elements some
and got a pretty good match, less than 1.5 to 1 SWR on it by shortening the
elements. Then a strong rain storm came last night and the SWR shot up on 30
meters to over 3 to 1 and the same for 20 meters a high SWR. I am suspicioning
that the old traps on this used antenna are sucking water even though I used
electrical tape to close and seal the end caps that were split and
deteriorated. Right now the SWR on 20 meters is very high and the SWR on 30 is
over 3 to 1. The other bands, 10 and 15 meters are as expected. So am I on
the right track in suspicioning the 20 meter traps? I have read that Cushcraft
traps can be disassembled and cleaned etc. Anyone familiar with the 20 meter
traps for the 30/40 add on? Please let me know as any info would be
appreciated.
Thanks in Advance
KB0GU
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