Before my tower came down I used a type of T on 160. Approx. 55 ft. Vertical
with 2 sloping top loading wires about 35 ft each. Fed on ground with inferior
radial system. Had a resonance (SWR wise) below the 160 meter band. It needed
capacitance. For a capacitor I used a long length of Teflon, thin coax @ 39
pf/ft (?)Actually coiled it up on a 1” form. Total capacitance was about 1000pf
+/-. It made the Z very close to 0 at lower band edge. It had a 2/1 SWR
bandwidth of about 100 kHz, which meant there was ground loss, though the VSWR
curve was beautiful. It worked fair, only because radial system needed to be
improved. Before I could do more, the tower came down after two wind events.
The coaxial capacitor held up under my 500 watts. It might have been RG-302 or
similar 50 ohm? Very thin, 1/8”?
Art., N2KA
Sent from my iPhone
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