----- Original Message -----
From: "Alan Melia" <[email protected]>
To: <[email protected]>
Sent: Wednesday, April 30, 2003 8:36 PM
Subject: LF: Re: strange condx
Hi Mal, thanks for the interesting report. I have looked at the darkness
shadow at that time using Geoclock, and it crosses the path at quite an
angle, approximately between Berlin and Helsinki. That means the
ionosphere
is probably still illuminated at around the Russian boarder. My guess is
that the early signal was a one hop path from the bottom of the E-layer at
about 100kms altitude. Later higher order paths become possible as your
end
of the path goes into darkness and these destructively interfere giving
very
deep sharp fades. It is surprising under present conditions that the
initial
signal was so strong as it is a "long hop". Two hop signals would normally
be stronger and more stable over that distance except that there is a lot
of
nightime absorption due to the after-effects of the geomagnetic activity.
This would weaken the two hop signals. Maybe that makes them of similar
strength to the one hop and hence the deep fade (cancellation when the
phases oppose)
Of course I could just be totally wrong....but it sounds like a good
story.
Tnx Alan for your observations, the only other explanation could be that
RN6BN lost a couple of FETS and suddenly took a dive because of power
deprivation.
Cheers de Alan G3NYK
[email protected]
----- Original Message -----
From: "hamilton mal" <[email protected]>
To: <[email protected]>
Sent: 30 April 2003 16:01
Subject: LF: strange condx
Yesterday early evening around 1900 z RN6BN was a very strong signal,
stronger than usual about S6 then about one hour later he suddenly started
to disappear, this is when I worked him on 137.7 QRS3, we have worked
before. Although weaker he was solid O copy and he gave me the same
report.
Shortly after we worked he disappeared totally on a CQ then re appeared,
perfectly readable but during the evening never got as strong as around
1900z. I have not noticed this rapid QSB on signals before on 136 khz
There
seemed to be some unusual propogation at this time.
YU7AR and OK1DTN were very strong with some variations on their signals
also
during the evening.
I also observed some DL acty and DK8KM on hellscriber or some variation of
the mode, solid signal.
73 de Mal/G3KEV
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