Bill,
I wrote to one of the relay stations with similar questions. Usually in
Colorado KH6 boom in on 15 and 20m even when condx are poor. Maybe the
arrays are fixed over the pole which would put the us of the side. If I get
a response I will pass it along.
Mike W0MU
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Bill Jackson
Sent: Monday, October 03, 2005 6:09 AM
To: towertalk@contesting.com
Subject: [TowerTalk] K7C - One-Way Propagation?
Towertalk Gang,
Here is an excerpt from one of the recent K7C dx'pedition bulletins,
regarding poor signal quality they appear to be experiencing on their end:
"Let's start with a technical consideration of which you should be aware.
As you already know, we are using vertically-polarized antennas very, very
close to salt water and with large radial fields. This makes our signal
launch angle very, very low - quite a bit lower than most
horizontally-polarized antennas on dry land. As a result, the K7C signal
has been reported to be very loud on the receiving end. This doesn't mean,
however, that you are just as loud here. All it takes is a couple of extra
"hops" from a higher launch angle and your signal will change from an
easy-to-work S5 to being undetectable. The K7C team has observed a number
of occasions when it is obvious that you can hear K7C easily, but on our end
the pileup is only an unworkable S-1 grumble. This is most pronounced at
the beginning and end of an opening so you may be hearing us long before or
after we can hear you. Marginal openings on the paths to Europe, the Middle
East and Northern Africa may be enti rely "one-way" - incredibly
frustrating for you to have K7C be as clear as bell, but not hearing the
most important DXer of all - you."
Does this explanation make sense? I would think that an antenna with a high
angle of radiation on transmit would also favor signals with high arriving
angles on receive. The amount of signal attenuation on a signal arriving at
a low angle at the station with the antenna transmitting with a high angle
of radiation should be equally diminished. Therefore the station with the
horizontal antenna over dry land should have trouble hearing hearing K7C as
well.
What am I missing here?
Even though I have managed to work them on both 80 and 40m, they have never
had what I would call a LOUD signal, compared to what I often hear from KH6
land.
73 de Bill
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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