To all of you going nuts trying to figure out [or defend your perception
of] the difference between a quad and a yagi...
The most important set of dB's is in the mind of the contester.
I remember a story about a contester at a multi who was told he was on a
dipole for 15-30 minutes at the beginning of a DX test while the owner
was finishing a repair, and then was told that the big beam was now
inline. The operator immediately switched from S&P to run and praised
the improvement. It was later discovered that the beam was in line since
the beginning of the contest, and the owner had been in the kitchen
getting something to eat, since he had been on the tower all afternoon.
PLACEBO effect is REAL. If we THINK we are loud, we ARE loud, because we
BEHAVE loud.
Truth of the matter, a point disputed by many, but a matter of record at
Bell Laboratories, approximately 3 dB is the threshold of reliable audio
differential perception for the average human being. Probably not a
human alive who can tell which of two tones was louder if the difference
was 0.5 dB. There ARE some transmission modes where an additional 0.5 dB
will allow a circuit to lock on signal and decode, but the human ear is
not such a circuit.
But if you THINK you are 3 dB louder you will ACT and THINK and DECIDE
louder, and your score will show it.
I told a well-known east coast contester that his new 40 meter signal
(great QTH and new 3 element full size beam) was loud. He wanted to know
why I thought it was loud. I had to convince him. I also told him that
when the time came for 40 meter JA opening, that he should not S&P, but
call CQ, because he WAS loud, and should ACT loud. In the contest a few
days later, he RAN JA's on 40 ssb from the east coast.
I once broke a pile-up for a rare multiplier on 15 cw that included some
big time multi's, loading into a 20 meter beam pointed the opposite way.
(Had suffered some Murphy-esque antenna problems and repairs were
underway.)
The thought was, if I can figure out where he is listening on the edge
of the pile up, dB's don't matter if I'm just loud enough to be heard.
THINK loud, think POSSIBLE, operate SMART. BEHAVE like you own the band,
and you WILL.
Biggest dB's of all are between your ears.
73 y'all,
Guy.
-----------------
Guy Olinger, K2AV
Apex, NC, USA
----- Original Message -----
From: Robert Shohet <kq2m@mags.net>
To: <towertalk@contesting.com>
Sent: Saturday, February 10, 2001 11:59 AM
Subject: [TowerTalk] Antenna Debate
> Gentleman,
>
> Far be it from me to take issue with those who more learned than I
when it
> comes to antenna modeling, theoretical gain analysis, wave patterns,
> electromagnetic theory, etc. I leave that to those who really know
their
> stuff like W8JI, W4RNL, W4ZV, etc.
>
> However, I will take issue with those who might believe that a "3 -
DB"
> difference between antennas (at the same height and at the same
location) in
> modeled antenna gain, actually equates to 3DB in a DX contest taking
into
> account all propagation paths, differing amounts of noise, propagation
> fluctuations, etc. Here is where the practical trumps the
theoretical, and
> personally I believe that whatever works best in the actual contest at
a
> particular time is all that really matters.
>
> I remember a rather lively discussion in Aruba many years ago with my
> friend, Wayne, N7NG, about the differences between two antennas that I
was
> using at KM1H. Wayne adamantly stated that there was only a 3db
difference
> between them, I said that under most condx there was a 1-2 S unit
difference
> between them and made the difference between running and feeling loud
vs. S
> & P and having guys CQ in my face.
>
> Who was right? Probably neither of us. The truth like always usually
lies
> somewhere in-between. Wayne was right about a 3-DB theoretical
difference
> I unfortunately don't remember what the antennas were now - probably
a TH6
> vs a 4L longboom 20 on a 42' boom - W2PV design), and I was right
about
> running guys and being loud.
>
> Being loud and running guys was more important in the contest, and I
would
> have gladly loaded up a rain-gutter if that really would have worked
better
> than what I was using.
>
> Lesson: Stay flexible and BE PRACTICAL! What works best at your
location
> for your radio purpose is all that really matters.
> Discussions on theory are a great way to learn and to build better
antennas
> but 3DB is rarely ever 3DB in a contest and gain figures should NEVER
be
> seen as absolute. Likewise, silly claims of 20DB gain over a 6L yagi
do not
> make one louder either and will never stand up to rigorous analysis
and
> study. I think it is better to enjoy building and experimenting with
> antennas, not fight about them.
>
> One more thing, using contest results from the 1970's to document the
> viability of an antenna in 2001, means nothing. Radio cndx are
different,
> radios are different, activity level is different, skill level and
> competition is different, contest rules are different, technology is
> different and operator motivation is different not to mention that we
are
> all 31 years older (OUCH!) than we were in 1970! If anyone is the
same
> today as they were 31 years ago, well, that would REALLY be something
to
> talk about.
>
> 73
>
> Bob KQ2M
>
>
>
>
>
>
>
> --
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>
>
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