Another issue worth considering is the possible negative effect on the
performance of the yagis on a tower from which slopers are suspended. I
found that replacing the top guy set on my tower with Phillystran made the
40m yagi on top of the whole thing "come alive." I had not recognized any
particular impact on the beam's performance with the previous guying, which
consisted of a 21-foot fiberglass insulator from the tower to the top of
the guy, then solid EHS to the bottom where it was grounded. But even at
that distance from the yagi, and no obvious resonance on 40, the sloping
wire clearly affected the yagi's gain or pattern (or both).
73, Pete N4ZR
The revised World Contest
Station Database
is online at www.pvrc.org
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