1st attempt timed out and was not delivered ????
Alan
----- Original Message -----
From: "Alan Melia" <[email protected]>
To: <[email protected]>
Sent: Sunday, September 04, 2011 3:22 PM
Subject: Re: LF: Weak signal on 137780.3
> Hi Markus, Jay and John,on some phase runs done a few years back there was
a
> continual drift in phase during the darkness period. Suggesting a steady
> increase in height of the "reflection level". This was on a short path
> probably only one hop. The path to Jay for you is probably several hops.
> There may be 2 3, and 4 hop paths involved generally these will change in
> length through the darkness period. I wonder if that effect could be
> explained by say the 3 and 4 hop paths summing and cancelling with the 2
hop
> path. There would also be a rapid resultant phase change as well for this
> condition, I think. ??????
>
> Alan G3NYK
>
> ----- Original Message -----
> From: "Markus Vester" <[email protected]>
> To: <[email protected]>
> Sent: Sunday, September 04, 2011 2:56 PM
> Subject: Re: LF: Weak signal on 137780.3
>
>
> Excellent Jay, thanks very much! I am really happy about this result.
> Attached is a spectrum graph, showing your peak at 3:16 UT, with about 12
> to 14 dB SNR in the 0.438 mHz FFT.
>
> Do I understand you correctly in that you transmitted a continuous
carrier,
> without a frequency step? Then the apparent 3.8 mHz shift must have been a
> transient propagational Doppler effect. Remarkably, this lines up with
> observations of John Andrew's tests in 2006, which had also shown two long
> stable runs, with a dip and rapid phase change inbetween. The dip seems to
> roughly coincide with midnight crossing over the middle of the path, but
I'm
> not aware of any simple physical explanation for this.
>
> BTW Your transmit situation must be similar to mine: I have about 200 W
> available into a Marconi antenna, which is about 0.1 percent efficient
now,
> and up to twice that in a cold winter night.
>
> Best regards, and thanks again for the test
> Markus (DF6NM)
>
>
> From: [email protected]
> Sent: Sunday, September 04, 2011 1:27 PM
> To: [email protected]
> Subject: Re: LF: Weak signal on 137780.3
>
>
> Markus
>
> The mystery signal was from WD2XNS ... you have the time and frequency
> perfectly correct and the color DF also provides corroborating evidence.
> Note that there was no break in the transmission. The frequency is
> controlled by a GPS disciplined oscillator (accuracy about 13 ppt).
> Transmitter power was 200 watts ... radiated power is not known. During
> winter, with frozen ground, additional radials, lower R and less foliage,
> the radiated power would have been about 0.5 watt. Expect last night's
test
> would be at least 3 - 6 dB (maybe more) below that level.
>
> Jay W1VD WD2XNS WE2XGR/2
>
> ----- Original Message -----
> From: Markus Vester
> To: [email protected]
> Sent: Sunday, September 04, 2011 4:45 AM
> Subject: Re: LF: Weak signal on 137780.3
>
>
> The mystery signal was received between about 0:15 and 3:30 on
137780.310,
> with a 3.8 mHz downward shift from about 1:30 to 2:15 - somewhat
reminiscent
> of a DFCW "GM". Greenish colour indicates southwesterly origin. The
attached
> screenshot was taken at 8 UT, timescale is 10 minutes per FFT.
>
> I checked the other available TA grabbers around 4 UT, but no trace of
the
> mystery signal.
>
> 73, and have a nice sunday,
> Markus (DF6NM)
>
>
> From: Markus Vester
> Sent: Sunday, September 04, 2011 5:39 AM
> To: [email protected]
> Subject: LF: Weak signal on 137780.3
>
>
> LF,
>
> there seems to be a signal on 137780.300 Hz, about 60 nV/m here.
> http://www.alice-dsl.net/df6nm/grabber/TAnarrow.jpg
>
> Wondering whose it may be...
>
> Best wishes,
> Markus
>
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