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....... Mork calling Orson ?
G,)
Sent: Monday, November 04, 2013 5:33 PM
Subject: Re: LF: Tasmania? Yes!
Hello Markus,
Thanks for the efforts and your analysis.
Your recent image (attached) is convincing for me. There has been no veto so i
think we can accept that as valid.
73, Stefan/DK7FC
Am 04.11.2013
00:20, schrieb Markus Vester:
Today Stefan and I got a long wav recording
from Edgar J. Twining, starting 2013-11-01 16 UT, shortly after the potential
reception of dashes from DK7FC in Orford, Tasmania. Signals from all
three EFR utility transmitters (DCF49, HGA22, DCF39) could be found in
the recording. Using the same default samplerate and LO settings that
Edgar applies on his grabber, the idle frequency from
HGA22 appeared to be centered on 5429.95 Hz audio, which is about 72
mHz lower than expected from the actual transmit frequency.
This offset is in good agreement to the
observed -75 mHz offset on the DK7FC signals, showing that this was
indeed a real reception.
Best 73,
Markus (DF6NM)
Sent: Saturday, November 02, 2013 1:59
PM
Subject: Re: LF:
Tasmania?
...
From my point of view,
the best contribution to a "proof" would now be verifying the
receiver's frequency calibration offset. On yesterday's screenshots, the HGA22
line seemed to be just half a pixel below the tick. Simply
by zooming in on it you could measure the offset much better, even
though the line is spread by some tens of milliHz due to the FSK
modulation. Last year I took some effort to measure HGA's idle
frequency in detail against a calibrated Rubidium source.
The result was 135430.022 Hz, with only very little
variation of a milliHz or so (see attached).
...
Sent: Saturday, November 02, 2013 2:31 AM
Subject: Re: LF: Tasmania?
Stefan, Edgar,
In my opinion this is a valid detection. It would
be very unlikely that pure noise would produce such a result, and
there has not been any indication of a spurious carrier on this
frequency in Orford.
The small offset in the frequency calibration
(about -75 mHz) is surely within expected tolerances of the
receiver's free running crystal oscillator. This is in accordance
with the Orford HGA spectrum, which shows the peak also very
slightly below the 135430.0 Hz grid line.
Best 73,
Markus (DF6NM)
Sent: Saturday, November 02, 2013 12:24 AM
Subject: Re: LF: Tasmania?
Hello Markus, LF!
Yes, i saw these 3 dashes (which are
"dits" on that QRG and time) in one line. And if they are from me, it must be
the end of the 7. And i was transmitting the 7 just to that time.
Did you
place your grabber image overlay onto Edgar's image so it fits the 3 dashes or
did you place it so that the time stamp fits to your time?
If "we"
call this a valid ID and detection, then these 16833 km are a new #3
world record distance on 2200m! (according to http://136.73.ru/h_qso/index.htm )
Do "we"?
Would others agree/disagree?
73, Stefan/DK7FC
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