N4UK writes:
>With 24 insulated radials laying on the ground Don
>observed a reference signal and I observed likewise.
>I connected 3 elevated 130 foot long radials at a
>height of 8 feet. The reference signal increased 2 db.
Did you look at the feedpoint impedance when you made these changes? That
should give you a big clue to the efficiency of the installation. With the
ground radials, I might suspect that the impedance could be higher than
expected (close to, or above 50 ohms?) which would generally indicate a
lossy system. With the elevated radials, you probably had an impedance
closer to 20-30 ohms, which is the correct range for verticals, especially
short verticals. My guess is that the ground radials were very lossy in
your installation.
A few years we did a fair amount of work on vertical testing and
installation for Team Vertical (6Y2A, 6Y4A, 4M7X), which you can take a look
at: http://pages.prodigy.net/k2kw Even for verticals mounted by the sea,
using elevated radials will still yield a more efficient antenna... (the
elevated radials provide an efficient current return for the vertical, and
the salt water is the conductive ground plane).
73, Kenny K2KW
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