Brian-K8BHZ explained a theory that seems (in my humble opinion) to conform
to things I've read in Bob Brown's book(s) on the subject. Brian writes:
(Brian is in MI and I am in MN)
*****************************
We are at rather high MAGNETIC latitude & are quite often affected by the
auroral zone affects, which others to the south don't experience. Although
many of the European & Asiatic countries are at even higher conventional
latitudes, we get hit because the magnetic pole is actually quite a distance
from the true North pole, and lies North of us!! The zero degree deviation
line ("directly" South of the Magnetic North Pole), comes directly through
the Upper Peninsula of Michigan, not far from me. As I am close to this line
& even slightly higher than you in conventional latitude, I suspect that I
have it even worse than you, if that's any consolation! You may have the
website to view the auroral doughnut and can see the offset affect, if not,
I can dig it up for you. I wonder if this may be one of the reasons that
W8JI moved to Georgia!!
*****************************
My personal view is that Brian is on to the real issue at hand. My antenna
is firing at 25-30 degrees and under the curtain. The DX is unable to skirt
under the curtain and ends up getting severely diffused on my end, resulting
in very low signal levels.
Right? Wrong? Where's Bob Brown when you need him... As to W8JI's motives
on QTH, only Tom knows for certain.
Ford-N0FP
ford@cmgate.com
----- Original Message -----
From: "by way of Bill Tippett <btippett@alum.mit.edu>" <K3BU@aol.com>
To: <topband@contesting.com>
Sent: September 26, 2002 8:41 PM
Subject: Topband: Bi-directional prop
> N0FP writes:
> >>The last few nights, the reports through polar paths are consistantly
> stronger than what I am hearing on my end. My noise floor is near S0 when
> the local power lines are not arching over. Path to Panama were
consistant
> with the reciprocity principle. Polar paths were more "one way." Finland
,
> Sweden, and Germany all reported better signals than what I am hearing
with
> similar power on both ends.
>
> Is it propagation or some anomoly with my new antennas?
> <<
>
>
> W8JI writes:
> >>I've been wondering how to test path direction differences for years.
>
> The only way I can think of testing path direction differences is to
> have systems with calibrated signal level voltage meters and antennas
> with identical properly focused patterns. The systems would also have
> to have known power and antenna efficiencies at each end of the path,
> and we would have to do a chart recording. <<
>
> K3BU notes:
> Contrary to W8JI assertions that propagation media is "linear" and
> reciprocal, there are situations when this is not so.
> One proof without chart recorders is that we often have a situation when
we
> hear the station well, but cannot get through (keeps CQing in your face -
> guhor). Later on situation can reverse or conditions allow QSO with
different
> signal levels. (unbelievers can insert "arguments" like local noise, etc.)
> Just don't bet on fact that if you hear station S7, he has to hear you S7
> when you have identical power and antennas. It is not much anomaly, it
> happens quite often. Just wait "your time" and propagation to get "right"
for
> both of you or maybe not. (I recall calling XZ1A for hours without getting
> peep or a point in the contest.) Refraction and ducting can 'splain that
> better than "mirrors" theory.
>
> Yuri, K3BU, VE1BY, VE3BMV
>
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