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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