Hi all yes Brian's plot shows a series of peaks from CFH. The reason it has
not been visible recently is not I believe due to propagation but more due
to inactivity. I also think the timing of the "blip" with a C3 flare is
probably totally coincidental as the radiation from the flare would only
affect the illuminated part of the ionosphere. Flare enhancement in daytime
follows closely the profile of the flux plot. Whilst the path from CFH to
Nurenberg passes quite a way further north than the path to Brian, it is
mostly in darkness I believe at that time. The Dst index has been climbing
for a few days now and has been well into positive values over the last 36
hours. This indicates to me that there are few "spare" electrons in the
Equatorial Ring Current to be precipitated or exchanged with the ionosphere.
These hot electrons are the ones that cause night-time absorption at LF (
and aurora), so night-times paths should be good at the moment. The only
negative factor is the level of QRM from lightning storms at this time of
year in the northern hemishere.
Cheers de Alan G3NYK
----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: 12 June 2005 09:08
Subject: LF: CFH (11/12 June)
Dear LF Group,
after several weeks of rather marginal levels, CFH showed a strong peak
between 02:00 and 03:00 last night (see capture). There were a couple of
weak
dashes on 137778.75 at the time as well. Perhaps coincidentally, the solar
x-ray
plot on http://www.sec.noaa.gov/today.html showed a prolonged period of
enhancement.
On 100 kHz, I have looked out for the announced LORAN pulses from Rugby,
but
nothing seen yet.
73 and all the best
Markus, DF6NM
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