To Jeff, Bob and others,
It was interesting to read of Jeff's conditions around 1100z on 20 March 1998.
At the same time I was listening on 20mx and the following was occurring:
(1) VK3MO working G4 on 14196.5 on the traditional Long path over South
America with the usual strong signals that Ian has.
(2) At the same time GW0 on 14195 below coming in over the North Pole
(slightly off short path) with an S7 watery signal. (not usual at this time
of the year)
(3) GH0 Jersey short path on 14260 with s5/8 signals.]
The band had the characteristic sound of what I call "hollowness of
expectedness" the sound that signals make just before the arrival of a
geomagnetic storm when signals tend to experience a strong peak.
I also was listening on other bands and could hear UW0 on 24 mhz (unusual at
this time), a few JAs on 18mhz and the usual Ws on 3.5 and 7 mhz. All
signals had that "hollowness".
On 1.8 mhz the atmospheric noise would have masked any reasonable signals.
As to the strange angle of arrival of signals that Jeff noted, it would be
enlightening if Jeff could obtain a printout of the ionogram nearest to his
location (or north) to see if any sporadic E was about, or for that matter,
any spread F. Sporadic E can certainly act like a giant 50 - 100 kms high
reflector in the sky. NO WONDER 160 MX and 6 MX operators come from the
same human factory mould!!!!
I have checked out the ionograms for the southern hemisphere for that time
(1100z) and the one for Hobart, our nearest location, certainly shows a
strengthening of the F and E layers with little ionisation at the 100 kms
level as one would normally have expected at that time - typical of the
onset of enhanced conditions.
If anyone is interested in observing the ionosphere conditions around the
Australian area, they can get the information from the following site:
http://www.ips.gov.au/asfc/aus_hf/ion_cat.html
You click whatever city you want and get the latest (usually every hour).
At the bottom of the ionogram you can click on the archive which will give
you the last 20 or so days of data.
So in conclusion, the conditions tht Jeff observed with KL7 were not only
restricted to his area. Corresponding abnormal conditions were noted on the
path from eastern VK up northwards across the Pacific and over the north
pole to Europe.
Cheers
Peter VK3QI
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