[TenTec] Radial Research: "Folklore"

[Rick - DJ0IP / NJ0IP]

Billy and I had a couple of off-reflector emails about why he thought my
post was "Folklore."

I said in a previous post, it is easy to build a vertical which is 12 to 18
dB better than your normal dipole.
I'm not backing down on what I said, but how I said it was very ambiguous
and might be interpreted wrong by others.

BILLY WAS RIGHT!
"As posted", my post could be wrongly interpreted by others to mean any old
vertical would beat any horizontal dipole.
This is certainly not the message I intended to portray.

Why?  As Billy said, it was ambiguous:
 - I did not state which band(s)
 - I did not describe the dipole
 - I did not describe the vertical
 - I did not describe the QTH
 - I gave no data to substantiate my claim
 - I didn't even say how I measured my results (shame on me)

I will restate my experience and fill in the missing information:

I have made identical experience in 4 different QTHs in the past 25 years,
dating back to 1987.
I will describe the 10 years living just south of Munich, 2 miles outside
the city limits, because during this time period I was specifically
investigating this horizontal/vertical scenario.
Munich is approximately 650m (2000') above sea level.

My QTH was rural, with houses east and west of me, but about 100m (330')
away.
I had a forest to the south, and a field and then Autobahn to the north.
My house was very old, made of stone and wood; almost no metal.
Admittedly, a very good QTH for any antenna located anywhere near a big
city.

The dipole was a very good quality dipole, built with 2mm stranded,
insulated copper wire, a W2DU current Balun, and about 75' of AIRCELL-7 coax
(similar loss to RG-213).  It had an 80m and 40m radiator tied in parallel.
The center (feedpoint) was 13m (40') high and the ends were about 10m (33')
high.  It was orientated such that its major lobe was towards stateside
(NW/SE).

The vertical:  Not so easy to describe.  There were many. It changed each
year.  The dipole remained up all year, the verticals were only installed in
the winter during contest season.  I was always trying different types;
ground radials, elevated radials, and short vertical dipoles fed with
openwire and matched through a link-coupled (Annecke) high-power matchbox.
One year I tried a strange "Moxon" vertical and it was not as good as the
others, though slightly better than the dipole for DX.

The bands were 80m and 40m.

As stated, I put these up every year for about 25 years, just for contest
season, but this document pertains to the results for the ten year period in
which I lived in the QTH described above.

Admittedly the horizontal dipole was too low for any kind of serious DX, but
German law limits height of permanently installed masts to 10m (33') unless
you apply for a building permit, and I was pushing my luck with 40' (no
building permit).  40' is a height which is low for 40m (DX) and much too
low for 80m (DX).

Measurement Methodology:  Simple; the S-Meter of a TEN-TEC OMNI VI+

RESULTS:  When working DX, such as stateside, the vertical, regardless of
which one I was using, was typically 2 to 3 S-Units stronger, for most
contest QSOs.  In this ten year timeframe, about 1000 such QSOs were made on
these bands.  But sometimes the horizontal dipole was better. That was rare
but it did happen.   EVEN MORE difference was found when working towards JA
or Asiatic Russia.  Here the difference was sometimes 3 to 4 S-Units or
more, but this was because it was off the end of the dipole.

Obviously the results were due to the difference between low angle radiation
from the vertical and high angle radiation from the relatively low dipole.
It's always that way, unless you have too much losses in your vertical
antenna system.

I DO NOT CLAIM THAT MY VERTICALS WERE OPTIMIZED.  At no time did I use more
than 16 ground radials or 4 elevated radials.

Important:  I did not use commercial trap verticals.  All verticals were
home-brew using fiberglass masts and copper wire.

I am confident that my results represent what is truly possible under the
conditions that I measured them.
It would be WRONG to imply that anyone anywhere else would have similar
results using these same antennas.
Local environmental influences will always affect your results.

HOWEVER, AND THIS WAS MY POINT ALL ALONG, being that I had a QTH which was
relatively in the clear, it did not take much elaborate work to build a
vertical that would substantially out-perform my low hanging horizontal
dipole for DX.  
YOUR MILEAGE WILL DEFINITELY VARY.

AND MY MAIN MESSAGE TO EVERYONE WHO HAS NEVER TRIED THIS IS.... HEY, JUST
GET IN THERE AND DO IT.  
Don't be scared off by too much technology.
Start simple and improve as you go.

Thanks to Billy for cleaning up my act.

73
Rick, DJ0IP