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Hi Edgar, LF,
this looks like a great project, and it's good to
see a live grabber from VK7 again. So with that extra distance you might reach
the top three in the DX list... unless Mike, Bob, or someone else takes the
challenge and picks up Stefan in ZL ;-)
Orford - that's surely a nice location. On the
occasion of attending a conference some 15 years ago, we were lucky enough to be
able to drive around the Tasmanian east cost for a few days. We were much
impressed by the beauty of the landscape, the clear skies, and the friendly and
easygoing manner of the inhabitants.
Are Stefan and you intending to focus on DFCW only,
or try other modes as well? Attached beneath is a short table, lining up
approximate sensitivities for a few weak-signal options.
Best 73,
Markus (DF6NM)
Mode norm.SNR SNR bandw.
duration remarks
dBHz dB mHz
minutes
carrier -18 14
0.4* >30 highly significant peak in 0.4
mHz spectrum
DFCW-90 -12
6 11* 42 marginal
"M" detection in spectogram
DFCW-90
-6 12 11*
42 fully readable "O"
Opera-32
-1 8 125
33 reliable decoding by Opera software
Opera-32
-12 21 0.5
33 correlation detection of a coherent
transmission
WSPR-15 -4 3.5
180 15 decoding by WSPRX
software
WSPR-30 -7 3.5
90 30 accelerated replay to WSPR
software
MFSK37 -9
14 3.3* 25 visual decode
or automated peak search
Notes:
- SNR thresholds are only
approximate.
- SNR referenced to carrier power (not average).
- normalized
SNR in 2.5 kHz can be obtained by subtracting 34 dB from dBHz.
* noise
bandwidth is 1.5 times the stated FFT bin width.
- duration to send
"DK7FC" message (19 dashes and 4 spaces).
- MFSK37 is absolute frequency
keying, sending one 5 minute dash per character.
Sent: Saturday, August 03, 2013 1:28 AM
Subject: LF: DK7FC Equinox reception
Hi,
During the last three Equinoxes I have
attempted to receive DK7FC's
signal at QE37pd, Moonah, Tasmania.
The
best result was achieved last April.
Refer to:
https://dl.dropboxusercontent.com/u/101251787/DK7FC%20reception.pdf
I
decided for next Equinox period, (20th September 2013), that I would
attempt
to better the distance previously achieved.
The results will be available
on the internet.
https://dl.dropboxusercontent.com/u/101251787/testIDC.html
At
present the equipment is set-up at QE37pd, and when possible Stefan
is
running test transmissions from 19:00 to 22:00 UTC.
By the middle of
August the system is to be set-up at Orford, on the
east coast of Tasmania,
to operate until the end of September.
http://no.nonsense.ee/qthmap/?qth=QE37wk
The
frequencies of DCF39 and HGA22 signals are also being monitored to
determine
the propagation.
So I invite members to participate by monitoring the
progress via the
web images.
Regards, Edgar
Moonah,
Tasmania.
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