My 100ft 45G was installed with 3 sets of guy wires. The top 2 are
Phililstran and the bottom ones are EHS but with the top insulated from the
tower.
I tried shunt feeding the tower for 80 and 160. On 160m the results were
excellent. On 80, I could not find a good tap, with some weird impedances
changing every foot, so I put a 80m vertical 3 ft from the tower. The
performance on CW was dismal (10 db below a 100ft high dipole to EU) and on
SSB was excellent (few db over the dipole). I measured the resonance of
each guy wire with a clamp toroid and one loop, and all had resonances
close to 3.1 MHz with SWR 1.3:1. So clearly the guy wires were messing up
and were preventing the match with shunt feeding on 80m.
I put 2 clamp-on toroids on each guy wire as high as I could reach with a
ladder. Each guy wire is now resonant around 2.7 MHz. The vertical's
resonance moved from 3.53 to 3.62, but there is a second resonance on 3.4.
So my question is what to do especially that the vertical was just a test
for 4 sq. Keep the toroids knowing that they will eventually crack since
they are exposed to vibration? Move to Phillistran? Or is there another
(simple) option?
Ignacy, NO9E
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