At 02:48 PM 3/6/98 +0000, Tom Rauch wrote:
>Myself, I'll go with a few actual direct comparisons over computer
>model "measurements" or loosely applied "FCC proof estimates"
>any day.
>
>I'm hoping to do some tests on 160 this spring, as I add a second
>tower in an empty pasture far from the present antennas. I'll let you
>know when and if I do that test.
>73, Tom W8JI
Hello Tom, and all others that have been involved in this thread.
Tom, you make some excellent points, and this is the best post I have seen
from you. Thanks for the insight. I look forward to reading the results
of your testing. Sounds great.
My reason for replying is to point out that the majority of us do not have,
and probably never will have, 1. the instrumentation 2. the time 3.
the physical facilites, to do the proper testing that you refer to.
The vast majority of us are AMATEURS, and our accomplishments correlate
very closely with the three points made above. Money helps, of course.
Most of us have to rely on the unscientific method of making direct
comparisons on the air. That is what I have done and continue to do.
My transmit antenna is a full sized 1/4 wavelength elevated Ground Plane.
Just picture in your mind the 19" spike for 2 Meters with it's 4 sloping
radials, enlarge it 80 times, and you have my antenna. The base of the
130' vertical is 1/8 wavelength above ground with 4, 1/4 wavelength caged
radials sloping out to the tops of 55' wooden poles.
The nearest station to me which has a "classic" ground mounted 1/4
wavelength vertical with 100+ radials is N6SS, Pres, in Prescott, AZ. That
location is about 300 miles west and a bit north of here.
Pres is my benchmark. His station and his operating prowess are very well
known. When my station can compare favorably with his, then I know that I
have done something correct.
In the January 1998 CQ 160 CW contest the log comparison between N6SS and
N5IA revealed the following. N5IA had more Qs and more Mults, but N6SS had
the higher score by about 5K, about 2% difference. N6SS "won" this two
station contest scorewise by virtue of having more 10 point Qs, primarily
by working more JAs from his more westernly location.
In the same contest in 1996, N6SS and N5IA were both copied by Vlad,
UA0ACG. Pres personally sent me a copy of a SWL report he received from
Vlad, who is in Zone 18. In the report Vlad says to Pres, "Ur RST contest
559/569 QSB. From W6/W7 RST 229/339. N5IA RST 569/579 CQ for Japan."
This is my experience and comparison of an elevated Ground Plane vs. a
ground mounted vertical with a full sized radial system.
73, and everyone have a good weekend. Milt, N5IA, in Southwest New Mexico
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