Re: VLF: A weekend for newcomers and advanced newcomers...

[DK7FC <selberdenken@posteo.de>]

Hi Paul,

Great work, as usual. Thanks.
-2.5 dB, that agrees with the Eb/N0 value of the 4 character message.
Alex has re-optimised the system again. New attempts for a message 
longer than 7 characters can be done here...
73, Stefan

Am 01.03.2017 10:13, schrieb Paul Nicholson:
> Stefan wrote (22nd Feb)
>
> > f = 8270.100000 Hz
> > Start time: 22.Feb.2017   18:00:00 UTC
> > Symbol period: 30 s
> > Characters: 8
> > CRC bits: 16
> > Coding 16K21A
>
>
> > ...delayed by 30 minutes :-(
> > Start time: 22.Feb.2017   18:30:00 UTC
>
> (28th Feb)
>
> > 8chmessage.wav
> > Maybe Paul can analyse it further
>
> The message is in there at Eb/N0 = -2.5 dB.
> Timing good.   Not sure about frequency yet, still sweeping
> (slowly, the PC is full of 16K19 trials).
>
> Error map
>
>  http://abelian.org/vlf/tmp/170301a.gif
>
> suggests better reception during the evening and
> it gets worse later, or maybe there's a slight
> frequency offset.
>
> --
> Paul Nicholson
> --