Hi Paul, VLF,
That's amazing! A 'SMS' via VLF over ~ 25 wavelengths distance on the 36
km band, from a fixed antenna, in less than a day and without stacking!
Again i think back to 2010 :-)
Such a result in late May! We used to say that VLF won't work in summer,
because of the high QRN levels...
I'm impressed!
73, Stefan
Am 25.05.2017 21:50, schrieb Paul Nicholson:
Stefan wrote:
> Well, let's try something for the record list again:
> f = 8270.100000 Hz
> Start time: 24.May.2017 20:00:00 UTC
> Symbol period: 10 s
> Characters: 160 ( 1 SMS length :-) )
> CRC bits: 10
> Coding 8K21A
> Duration: 22h
Copied
"THIS IS THE FIRST SMS SENT OVER VLF BY RADIO AMATEURS.
THANKS TO PAUL NICHOLSON, DL4YHF AND DF6NM FOR SOFTWARE
DEVELOPMENTS. JOIN IN THE EXPERIMENTS! 73, DK7FC"
Rank 0, constant reference phase;
Eb/N0 = +0.6 dB;
BER 27.3%;
carrier S/N: 30.17 dB in 12.6 uHz,
-18.81 dB in 1Hz,
-52.79 dB in 2.5kHz;
That's a new record message length for VLF.
--
Paul Nicholson
--
|
