Hi Stefan, VLF
I got your signal in JN64bw, dear Stefan. Depending on the QSB and/or
QRN, you're peaking 15dB over noise. Fantastic! :-))
I'm using my LF antenna tuned on your QRG with a (approx.) 200mH coil.
The 17470.5 signal (locally generated by a GPS disciplined DDS) is
used for Spectrum Lab SR correction.
Schematic and capture attached.
Congrats, Stefan, and keep up the good work!
All the best,
73 de Riccardo IW4DXW
2017-11-26 0:40 GMT+01:00 DK7FC <[email protected]>:
> Hi VLF,
>
> Since 23 UTC a 700 mA carrier is running on 17.4701 kHz!
>
> It is a little surprise to the VLF community i think ;-)
>
> Legal? Yes:
> http://www.iup.uni-heidelberg.de/schaefer_vlf/VLF/17,47kHz_Sonderlizenz.jpg
> Actually the document has 3 pages but the other ones are no so relevant.
> My ERP is limited to 5 mW. I did not request more because more isn't
> possible anyway with this antenna.
>
> I wound a big single layer coil with 0.5 mm enameled wire on a PVC tube with
> 315 mm outher diameter.
>
> 0.7 A is just a first careful step. The coil is designed to hold 1.5 A 'key
> down'.
>
> The carrier will run the whole night and even tomorrow at daytime.
>
> Worldwide reports are welcome ;-)
>
> It is not sub-9-kHz but still VLF, the 17 km band!! So give it chance :-)
>
> The tree has still some solar power to stream the signal from the EW loop
> down to the city, so there is a feedback spectrogram at
> http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html
>
>
> 73, Stefan
>
> PS: I still can hear that tone of the coil. It is terrible! Be happy when
> you are older than me!
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