Hi guys,
Looking for the voice of wisdom and practical experience here.
Last weekend I put up my 5/5 stack on 15 at 40/80 feet, with a 105
Hygain 8 feet above the top antenna.
I had gotten the info off the Hygain homepage on modifying the antenna
for optimum CW performance.
At 2 electrical half waves of coax the 10 meter SWR is no better than
1.8:1.
We pulled it all down and on 4 foot saw horses the SWR is fine, although
the curve is a bit low (to be expected on the gnd). I hung the antenna
by the gin pole rope vertically on the side of the tower with the
reflector about 8-10 feet off gnd. SWR is fine. 1:1 at 28.025 or so.
Nice and broad, but not flat, which would cause suspicions.
Any hints?
My concerns are that my 15 is on a 36 foot boom, close to a 10 meter
full wave. But, the boom would be at right angles to the 10 meter
elements, kinda like a 40 meter rotated 90 degrees.
I'm 99% sure it interaction, not some mechanical problem.
If it is the boom lenght of the 15, I could extend some alum tubing out
one end or both ends to make it 40 or so feet.
I would like some advice from those in the know. These antennas are to
large to be putting up/down multiple times, because of my errant
speculation. Besides it wears out the help.
After several tiring hours, we were back at square one, with a tower
with no antennas on it! (had to bring the 15's back down to add an inch
and half to get them down where they belong; 21025).
Any thought would be appreciated.
73 de Steve, NJ4F
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