>From: "Charles Hutton" <charlesh3@msn.com>
(Re the ground wire laid directly under the Beverage)
>**** From the point of view of induced signal level, this will (depending
>on
>local soil) either do nothing or cause reduction of induced wavefront tilt
>and therefore the signal level for low arrival angle signals. From the
>point
>of view of terminating the antenna to make it unidirectional, it wouldn't
>be
>necessary. I can't imagine why this is recommended so if you run across any
>further explanation, I'd love to hear it.
Vic, W1WCR says that the classic Beverage is designed for groundwave or
extremely low angle skywave at LF and VLF, and is dependent on the wavefront
tilt to induce signal voltage into the wire. He maintains that at 1.8 mHz
and higher, reception is primarily by skywave arriving at 15 degrees or
more, so the wavefront tilt already exists due to the higher arrival angle,
therefore the wavefront tilt produced by the inferior conductivity of bare
soil is not needed. He goes on to maintain that since local electrical
noise is propagated by groundwave, by using the wire, the wavefront tilt is
reduced or eliminated and therefore the antenna more effectively rejects
local noise.
I tried both ways, and if anything, my noise pickup was higher with the
ground wire. However, my wire was bare, not insulated.
Don K4KYV
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