I have used a slightly less ambitious antenna Ed for 3 years now .
I use a 76ft vertical with a base tuner for 80m.
In parallel with the vertical are 2 x 24 ft verticals spaced about 18in
with 18in of ali tube connecting them at the top.
For 160 I simply switch in these verticals in line with the main antenna
and straight into the heliax feeder (300ft of it!) via a 3in diameter coil
(12 turns).
Result is very low SWR and a bandwidth of about 50 kHz.
This antenna really plays on 160 - HC2SL, VP8, TX3D, TX4T are recent
catches on the band.
The earth system consists of 50 x 66ft radials - it was after all
originally designed for 80m only ):
Just my couple of cents worth.
Nearly forgot - it is VITAL that the 2 linear loading elements do not move
in any windy WX because the SWR will vary wildly (I gess thru coupling
with the main vertical); they are guyed with 4 guy ropes (each with an
insulator at the top).
73 Cris
GM4FAM
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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