Topband: "Linear Loading" & 160-Meters

[cris at gm4fam.plus.com]

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