Jose,
Interesting paper, I'll have to poor over it some more to digest it.
Thanks,
Jim, KR9U
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of N4IS
Sent: Tuesday, December 04, 2012 9:05 PM
To: 'Doug Renwick'; 'Robert Briggs'; topband@contesting.com
Subject: Re: Topband: one- way propagation
Here some interesting paper about LF MF polarization
http://www.ann-geophys.net/22/1705/2004/angeo-22-1705-2004.pdf
This paper, High-latitude propagation studies using a meridional chain of
LF/MF/HF receivers
>>
Fig. 5. (a) Polarization of 50-5000 kHz signals recorded at Churchill,
Manitoba, on 1-2 October 1997. White pixels indicate left-hand polarization,
black pixels indicate right-hand polarization, and gray pixels indicate
indeterminant polarization. (b) Power spectral density of the same 50-5000
kHz signals. Received signals above 1MHz are predominantly left-hand
polarized except in the interval 09:00-12:00UT, 1-4 h before sunrise, when
righthand waves dominate at frequencies above about 3Mhz.
>>
Figure 5 shows a possibly related effect occuring near the dawn terminator
but involving wave polarization. The bottom panel shows a spectrogram of
50-5000 kHz signals recorded at Churchill, Manitoba, for 20 h, starting at
20:00 UT on 1 October 1997, a geomagnetically quiet day for which the
signals show the usual diurnal pattern.
>>
7'3 N4IS JC
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