Hi Stefan I think that maybe the right approach. I think you may find that
the "perceived wisdom" on fading rate v QRSS speed is based on relatively
short paths. I suspect it may well be very different at real DX range, that
is several hops.......>6000km. There obviously is some sort of a problem
because the wavelength is much shorter than 136kHz so the phase changes more
rapidly with ionisation and "apparent refection height" but you need two
"modes" of nearly equal strength to get extinction. This may not be so
prevalent at long ranges on 470kHz. The experiment will be very interesting
if you can start to leave traces on distant grabbers.
Alan
G3NYK
----- Original Message -----
From: "Stefan Schäfer" <[email protected]>
To: <[email protected]>; "Vasily Savchenko" <[email protected]>;
"Garry and Linda Hess" <[email protected]>; "Douglas D. Williams"
<[email protected]>; "Andy - KU4XR" <[email protected]>; "Edgar J Twining"
<[email protected]>
Sent: Monday, February 11, 2013 10:57 PM
Subject: LF: Considerations about wide DX experiments on 630m and tonites
QRSS-60
MF !!!!!!!!!!!!!!!!!!!!!!! ;-)
Edgar in Tasmania was recently asking if i have some plans about DX
experiments on 630m. Well that is a path of > 16000 km. However we do not
have real experience if that is easier than 2200m or rather impossible.
At least i know that there was not even a single decode by UA0SNV in my MF
WSPR and QRSS tests so far, while it is no problem on LF (OK my MF signal
is weaker than my LF signal). Thus i would guess that it is much harder to
get some traces of a signal on 630m. We will try anyway!
I'm starting to run a QRSS-60 transmission on 476.172 kHz (+- a few Hz)
for the night. Maybe someone across the pond will catch something. We, or
at least i still have no experience about the QSB problem on very slow
QRSS transmissions on MF. It would be interesting to see a spectrogram.
On air in a few minutes.
73, Stefan/DK7FC
PS: No, not only beacon transmissions, i've just had a > 1 hour long CW
QSO with PA0LCE and DK6SX/p! Also contacts to OK2BVG and S57A.
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