I have an Easyway HD 40 (41') crank-up tower that I'm trying to shunt-feed
for 80 meters. It has 12' of aluminum mast exposed above the tower with a
TH5MkII at 42' and an A3WS (w/ 30m kit) at 52'. It also has an XR-300
2m/440 antenna attched to the top. The base is a finned pole which is
firmly implanted about 7' in the clay soil. I have strapped the mast to the
tower and connected the crank-up portion to the bottom portion with wire to
insure a good electrical connection. I have an aluminum tube connected
which holds the matching wire (#10) approximately 38" from the tower to a
box with a Jennings CVCC 2500 vacuum variable capacitor (series fed) which
I've used to get a 1.1:1 SWR. The tower is loud compared to my beverage,
i.e. it doesn't sound like a dummy load. I'm not real thrilled with its
performance on transmit.
Can anyone tell me if the base in the ground affects the performance? Given
the above conditions, what is the best height and offset for the matching
wire? Any way to improve it, or should I give up and throw up some more
dipoles?
Thanks in advance for any advise.
73,
Steve K4WA (ex-KR4DL)
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