Hi Dave,
I suspect your problem is similar to my initial 160m Inverted L
installation - that being the part about your radiator sloping down to
25'. Due to problems very similar to yours, I eliminated any downward
slope I had initially, and made the whole thing horizontal to the earth,
and things (minimum SWR and bandwidth) improved a great deal. I realize
this is easier said than done in a lot of cases - maybe you can tie off
to a distant tree? Right now, my Inverted L is tied off to a tall tree
at the back edge of my 12 acre field - some 300 feet+ from the feedpoint
with a lot of darcon rope.
Dan KK3AN
Dave Novoa W4DN wrote:
I built an Inverted L for160 meters following K2AV's intructions for
the FCP, using the Balun Designs' isolation tranformer. It resonates
around 1813 kHz (that's OK with me) but the SWR is 1.9:1 minimum,
which my Yaesu Quadra amplifier does not like. The feed point is at
8.5' high, 25' away from the tower. The antenna wire, from DX
Engineering, runs up to about 67', then slopes down to about 25'.
There is a 4 element 20-meter Cushcraft yagi about 3' above the apex
of the wire on a 70' crank-up tower. What could be the problem that
causes the high SWR? Any advice is apreciated.
73,
Dave, W4DN
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Topband reflector - topband@contesting.com
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Topband reflector - topband@contesting.com
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