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Stefan
Visible at 1721 utc -131 dB
QRS 600 DFCW
de mal/g3kev
----- Original Message -----
Sent: Saturday, November 26, 2011 5:16
PM
Subject: Re: VLF: 8970 Hz transmissions,
soon again here
VLF,
Am 26.11.2011 17:55, schrieb Markus Vester:
Once more, Paul Nicholson is showing a good
trace:
Wow,
yes, very good!
Well, the system runs on the GPS locked system now
since 17:00 UTC and i'm running 780 mA on 8970.00000 Hz. Will go for dinner
now and leave the system running some hours. The WX looks quite useful, no
rain, poor wind and no fog! Maybe i will even run it overnight until tomorrow,
transmitting a streight carrier at 350 W RF. Can't do more unfortunately, due
to the cola-cap ;-)
Now as the signal is locked and non-drifting there
may come up something on the 6000-windows...
Maybe Paul or others can
do some calculations, estimating the ERP? I think it should be in the range of
200 uW. Up to 6 dB can be added in further tests, i hope.
Markus, a S/N
(better S and N ;-) ) plot on your side would be interesting. My ERP should be
constant now so we can observe the QSB, caused by propagation...
A
photo of the todays arrangement: http://dl.dropbox.com/u/19882028/VLF/DSC04268.JPG
73,
GL, Stefan/DK7FC
... well done!
Markus
Sent: Saturday, November 26, 2011 4:33 PM
Subject: Re: VLF: 8970 Hz transmissions, soon again
here
Stefan,
around 15:00, your sig on 8970.008 was
visible in Nuernberg, peaking ~ 20 dB SNR in 0.48 mHz.
Viel Glück,
Markus (DF6NM)
Sent: Saturday, November 26, 2011 3:57 PM
Subject: Re: VLF: 8970 Hz transmissions, soon again
here
VLF,
I'm now running 350W into the system and get
about 0.8 A antenna
current. Strong audible partial discharges occurr on
a parallel fixed
plate capacitor, spaced by 3 cola bottles (0.33l ;-) ).
At 550 mH i have
25 kV rms on the antenna and coil which seems to be no
problem at all.
The frequency is still a bit unstable since i took
the DDS VFO which is
more comfortable to find the resonance. I will now
try to slightly QRO
and then apply a fiber optic cable carrying the GPS
locked frequency
coming from the PC/SpecLab, hopefully without to many
phase glitches.
Currently i may have an offset of some 20...30 mHz and a
slight drift
but it is a first successfully test :-)
73,
Stefan/DK7FC
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