Hi Markus
Good signals here too in 424uHz and 125uHz (peaking 10dB over the
noise) alongside Henny and Uwe.
Nice to see VLF busy!
73 Chris G3WCD
On 28/03/2012 07:50, Markus Vester wrote:
The carrier was on air continuously from 20:26 to 6:36 this
morning.
Thanks very much to Lubos, as well as to all other live
grabber operators. As far as I can see, traces appeared at
DK7FC, G3ZJO, OK2BVG, and Paul Nicholson.
Best 73,
Markus
-----Ursprüngliche Mitteilung-----
Von: Lubos OK2BVG <[email protected]>
An: _RSGB_LF <[email protected]>
Verschickt: Mi, 28 Mrz 2012 4:24 am
Betreff: RE: VLF: DF6NM on 8970.002
Hello Markus, VLF!
Your signal is nice visible on my grabber in QRSS6000
and traces in QRSS600. In the 6000 window is evident,
that we did our VLF QSO in time, when the noise
conditions were not the best.
I have written an article about our qso in Czech. It
will be publised in a ham magazine "Radioamater", common
known in The Czech and Slovak republic. Some hams would
be encouraged to find VLF band by the report. :-)
73!
Lubos, OK2BVG
To: [email protected]
From: [email protected]
Date: Tue, 27 Mar 2012 17:22:42 -0400
Subject: VLF: DF6NM on 8970.002
It's a beautiful night! At 20:25, I have
started up a straight carrier on 8970.002 Hz (DHO
locked). If all stays well I will leave it on
until after sunrise.
An interesting observation on the side: In the
first few minutes, I drove the amp up to 400 mA
antenna current. A little corona became visible
near the ends of two of the three topload wires -
it wasn't very bright, not unlike 3rd magnitude
stars when viewed from the ground 10 m below. But
the 9 kHz sound from antenna itself could be heard
quite loudly, which is a potential
cause for neighbourhood trouble.
Then I reduced the drive to 350 mA where the
corona disappeared completely. So did the noise,
the antenna became absolutely quiet! All that was
left was a little noise from the coil in the
dustbin on the balcony, and the transformer
indoors. Thus the predominant cause for a
squeaking antenna must be corona. The fact that it
can be heard at 9 rather than 18 kHz demonstrates
that the discharge must have an asymmetric
dependence on the voltage polarity.
At the same time, wideband electrical noise on
the nearby LF grabber antenna went down by 20 dB.
BTW If you like you can actually read my VLF
frequency from an alias line on the LF TA grabber:
It is created by the 24th VLF harmonic,
intermodulating with DCF 77, thus appearing on 24
x 8970.002 - 77500 = 137780.048 Hz.
Best regards,
Markus (DF6NM)
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