"monster beam vs vertical"

[DOUGLAS ZWIEBEL]

Doug Pearson, KØDXV, commented about his experience with a GP vs a "low" yagi.

For DX, your experience confirms theory.  Horizontal antennas depend
upon height above ground for a "low take off angle."  At 25 feet, most
of you 20m yagi's signal was pretty much "straight up."

A GP, as you described is nice for DXing for a couple reasons:  First,
low inherant angle of radiation.  Second, vastly lower ground losses
than a ground mounted vertical with similiar number of radials.
Third, "friendly" input impedance.  The height over ground for the GP
base should be at least 1/4 wave, but less also works (as you found).
My comments are with respect to 1/4 wave (full or trapped) verticals.

The trouble with ground mounted verticals (and hence) radials is that
there are typically high ground losses.  If you have enough radials,
you can overcome that, but then you have a rather LOW input impedance
which must be (should be) closely matched.  A "good match" according
to an SWR meter in the shack on a ground mounted vertical with few
radials just means that you are heating the soil (high ground losses).

Of course, for "close in work," a low horizontal antenna will
outperform any vertical polarized antenna.  For bands like 160, that's
one of the nice (comforting) aspects.  If your horizontal antenna is
at 30 feet or 60 feet, it just won't matter...both will pretty much
behave/perform the same for both DX (poorly) and local (much better).

IN summary, while the simple 1/4 wave vertical has substantially less
free space gain than a 2 or 3L yagi or quad, when put over ground, the
amount of energy at the low angles for a vertical or GP may well be
substantially more than what you have with your "low" yagi/quad.

Sometimes less is more.

de Doug KR2Q
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