Re: Re: Re: VLF: DJ8WX 8270.004 Hz

[uwe-jannsen@kabelmail.de]

Hi Paul and Markus,

the chaos at 0200utc seems to be confirmed bei Pauls phase measurements: 2014-01-19_02:00:00 0.23 fT -171.5deg, with 171,5dgr as the biggest anomality.

Markus, the aerial hasnt been changed, but the output pwr has been rised by 100W to now 600Wrms.
the antenna current is unknown. I lost up to now three instruments by trying. they changed to coal.
GL
Uwe

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Von: rsgb_lf_group@blacksheep.org
Gesendet: 19.01.2014 13:18
An: rsgb_lf_group@blacksheep.org
Kopie: paul@abelian.netcom.co.uk
Betreff: Re: Re: VLF: DJ8WX 8270.004 Hz

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Attached are four stacked spectrograms of Uwe's signal as received by Paul Nicholson, DF6NM, OK2BVG and PA1SDB (top to bottom), scaled to the same time and similar frequency scales. The steps around 2 UT seem to have left a gap at OK2BVG and DF6NM. In a direct mail, Paul has sent a series of phase measurements in half hour intervals, which seem to corroberate the assumption of a phase step sometime around 2 UT.

 

The improvements of Uwe's signal at PA1SDB over the years is indeed impressive. Uwe, can you perhaps comment on your antenna size and current, then and now?

 

Very nice work!

 

Best 73,

Markus (DF6NM)

 

From: uwe-jannsen@kabelmail.de

Sent: Sunday, January 19, 2014 12:49 PM

To: rsgb_lf_group@blacksheep.org

Subject: Re: Re: VLF: DJ8WX 8270.004 Hz

Hi Peter,

There has been chaos around 0200utc:

 

2014-01-19 02:00:12  PPS zero-crossing too flat

2014-01-19 02:00:12  Timestamp didn't pass plausibility check !

...

 

I don’t know why. seems most of the satellites where asleep.

 

until coming night

Uwe/dj8wx 

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Von: rsgb_lf_group@blacksheep.org
Gesendet: 19.01.2014 11:01
An: rsgb_lf_group@blacksheep.org
Betreff: Re: VLF: DJ8WX 8270.004 Hz

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Hello Uwe, Markus, VLF !

 

I just took a "look back in time" in my 2012 and 2013 log's (www.qsl.net/pa1sdb) and I think over the last two years there is a large
rise in signal level when I take a look at DJ8WX his signal. The trace in some saved Spectograms in 2012 and 2013 are not that

impressive as they are right now. 

 

Look at the trace in the spectogram above. Impressive !!!

I have to do research if those "glitches" are at the TX or RX side...

Do you recognise that glitch at about 2 h Uwe ? (in your debug log ?)

I'm not at home this weekend, so I can't tel you the exact time right now.

 

 73's Peter - PA1SDB 

www.qsl.net/pa1sdb

 

----- Original Message -----

From: Markus Vester

To: rsgb_lf_group@blacksheep.org

Cc: Paul

Sent: Sunday, January 19, 2014 10:01 AM

Subject: Re: VLF: DJ8WX 8270.004 Hz

Hi Uwe,

 

great signal here, better than ever! On my grabber http://www.df6nm.de/vlf/vlfgrabber.htm it's well visible in 478 uHz, and even traces in the 3.8 mHz "600" window during the early morning hours. The SNR would probably have been sufficient for an Opds-4H detection, but I'm glad you just left the carrier on.

 

I had fixed my frequency offset and you were spot on 8270.004, albeit with occasional transmit phase glitches widening the 42 uHz trace a bit. Sorry about the apparent 0.8 mHz up shift after around 3 UT, it is an artefact caused by a too narrow setting of samplerate tracking tolerance (0.2 ppm).

 

Thanks very much for this test! It's a pity that Mal hadn't left his RX on overnight.

 

Best 73,

Markus (DF6NM)

 

From: uwe-jannsen@kabelmail.de

Sent: Saturday, January 18, 2014 10:56 PM

To: rsgb_lf_group@blacksheep.org

Subject: Re: VLF: DJ8WX 8270.004 Hz

Hi Markus,
just now reading your mail. the switch off time was some min after you sent it..
sri for that.
now the TX will stay on the air until tomorrow abt 0900utc.

Hopefully Mal reads this.

GL

Uwe

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Von: rsgb_lf_group@blacksheep.org
Gesendet: 17.01.2014 22:36
An: rsgb_lf_group@blacksheep.org
Betreff: VLF: DJ8WX 8270.004 Hz

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Uwe is again producing very good traces on the European grabbers. Even in my noisy location I am now getting a nice peak in the 42 uHz FFT (slightly higher due to an uncorrected 0.25 mHz error in my frequency readout).

 

Uwe, do you intend to stay on longer tonight?

 

Best 73,

Markus (DF6NM)