Firstly, many thanks to Markus DF6NM for his fascinating suggestion that
the signal variations from stations close to the Alps may be 'speckle
patterns' of received strength. This certainly seems a plausible explanation
and the figures Markus used are of the right order of magnitude for what is
being observed. This is another example of the type of 'research' which is
ideally suited to Amateur LF work, where we have a number of keen observers
within this group distributed over a large area. It would be interesting
if we could gather some more formal data on these signal variations and try
to establish whether they do in fact conform to some sort of speckle theory.
Secondly, hearty congratulations to all those who have made the excellent
recent achievements on 73kHz. I'm really pleased to see the 'old band'
getting a much deserved new lease of life before we loose it, especially
considering the somewhat greater challenge that 73kHz provides (both in
producing a good signal and also in receiving it!). As some of you know, I
suffer very badly on receive here, as I can actually see the Rugby antennas
from my roof. This had more or less totally discouraged me from putting in
the necessary work to get a signal out on the band in the short time we
have left. Obviously the progress and experience on 136kHz has been used to
great effect, both by the UK stations transmitting and especially by the
operators in other countries who now have excellent LF receiving systems -
another example of the wonderful co-operative spirit of this group, where
the overall results are much greater than those of any individual; something
I'm particularly grateful to be part of.
With all the fun people are having on 73, I might just be tempted to dust
off the NOV [73kHz licence extension] and take another look.......
Regards John G4GVC