Hello Jim:
With a flat SWR on 160, I think something must be wrong. I shunt-feed an
80ft tower with a 5 el 20 mtr yagi at 80ft, 15 mtr 3 el at 90 ft and 10 mtr
el at 100 ft. My shunt feed is tapped at 32 ft and is made of 1/2 inch
conduit and is spaced at 3 ft. I use an Omega match with 2 x 500pf vacuum
variables @ 7.5kV. They tune at about 300pf each.
The 2:1 vswr is only about 30kHz. Several others near St.Louis do the same
on shorter towers and have to vary the length of the Omega rod. They all
work great.
The flat VSWR means something must be a wrong. How do you work out with it ??
An amplifier is a must on top-band..
73 de Price W0RI
P.S. My lot is 90 X 140 ft and much metal connected to the base of the tower.
Water pipes, in ground swimming pool, many ground rods and a Poly-Phaser
grounding system. It does work well, If I could only hear as good. 132
worked on Top-Band de Price
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