I've been following this thread with a bit of interest. The following has
been my experience.
When I moved to this hilltop QTH in 1989 I decided that I would never
again use a vertical. Don't misunderstand; the vertical worked fabulous
at my old low elevation, lots of swamp QTH. But I had no intentions of
going thru the installation of 25,000 feet of radials again.
This QTH is on solid granite with a negative horizon slope in all
directions.
I installed a 160M Inverted V with the apex at 55' and the ends at 3'
above ground as a temporary antenna prior to tower construction. That low
antenna worked 3Y5X on Bouvet on 1 call thru a monster pileup. Late
evening QSO 0301Z.
Later that year (1990) the 160' tower went up and the inverted V went to
the top. ( The granite was only 8 to 14" down at the tower base.) For
the next 4 years I had no real problem working DX but I realized it did
not have the punch of the old vertical. Waiting in line in a pileup was
commonplace.
Finally I decided to try a vertical again but with elevated radials since
I had been hearing lots of good reports about them.
The result was a #12 wire hanging from a top guy wire and about 25' from
the tower; the bottom sloped out to 65' from the tower. Initially I used
6 radials.
The results exceeded my expectations. At no point was any DX better on
the horizontal; most times there were S units of difference in favor of
the vertical. When possible I ran numerous A:B tests with DX...all hours,
all paths.
After several months I added a second vertical and phased them for NE or
SW endfire plus broadside figure eight.
The horizontal excelled out to about 2000 miles or so.
Now...I'm wondering if geographic location is a factor since New
Hampshire is very often impacted by the auroral zone. Absorbtion is a way
of life here; quite different from a few hundred miles to the south of
me, Australia, etc.
I also wonder if the horizontal was too high and the elevation lobe was a
factor. With no real ground it is hard to model exactly what the
elevation lobe is. What is the true RF elevation over rock?
The performance at 55' makes me reconsider the ducting theory again since
the radiation was straight up.
Maybe it is time to try that 55' height again !
Hopefully others will share experiences and ideas. Obviously one size
does not fit all.
73 Carl KM1H
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