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Date: Fri, 29 Apr 2016 22:43:26 +0200
From: DK7FC <selberdenken@posteo.de>
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Subject: Re: VLF: EbNaut transmission on 8270.1 Hz again and again
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Hi Paul,

Yes, it will be interesting. Just 4 hours are gone now, i can't await 
it! ;-)
What about the phase of DHO38, is it useful to get a rough idea about 
the phase changes?
For slower modes (taking more then 12 hours), could it be useful to 
insert non-keyed sections to make a phase check each 2 hours or so?
Maybe it will be possible to develop a technique to calculate the 
behaviour of the terminator by watching given (msk) signals close to the 
transmitter, maybe even 2 or 3 of such reference signals.
12 hours is nothing! You remember my QRSS-60000 transmission, my 
callsign sent in 10 weeks! :-)
100 GB RAM, that's extreme. Certainly interesting but i would rather 
like to go a step closer to communications which are manageable for more 
people.
During a yesterdays walk through the forest i got some ideas about a 
QSO/beacon config for EbNaut. But i will describe that in a separate 
mail/topic, following...

73, Stefan

Am 29.04.2016 22:21, schrieb Paul Nicholson:
>
> > 27 hours will not be easy.
>
> Indeed, four terminators to cope with.  Half the message
> will have daytime phase and half night time phase and
> a mess in between.  No chance of a decode if day and night
> phase differs by more than 90 deg (which it probably will).
>
> So I will have to get a nominal phase from LWPC or my
> own modeling program (or just guess) and use that to EQ the
> signal before decode.
>
> An interesting challenge!  Thanks Stefan
>
> > Start: 29.04.2016  16:00:02
> > Period: 40
> > Length: 45 (!)
>
> No problem with the length, and for future tests like
> this, why not run a 16K code (with half symbol period)
> and with longer constraint length, eg 16K25A?  The
> decoder will need about 100 Gbyte RAM for that, but
> that's ok, I just use a big AWS Xeon with 36 cores and
> a ton of RAM.   The extra bit of coding gain is worth it
> and might make all the difference.
>
> -- 
> Paul Nicholson
> -- 
>
>
>