Re: VLF: 300 mA on 4470 Hz, 67 km band

[DK7FC <selberdenken@posteo.de>]

Hello Paul,

Very nice! Thank you for the reports.
If you got +3.8 dB from that message, then we can expect up to 10 
characters per night between us (using twice as long symbols and 
start/stop times optimised for our path), so the 100 character message 
is realistic between us! :-)
We will try that but it may take a few weeks before we can begin...

73, Stefan

Am 19.01.2018 09:26, schrieb Paul Nicholson:
> Stefan wrote:
>
> > f = 4470.100000 Hz
> > Start time: 18.JAN.2018  16:00:00 UTC
> > Symbol period: 60 s
> > Characters: 2
> > CRC bits: 16
> > Coding 16K23A (NEW)
> > Duration: 13h20min [hh:mm]
> > Antenna current: 300 mA
>
> > Unintentionally the message was sent with 30 second
> > symbols this night.
>
> Good copy in Todmorden.  Based on last night's carrier,
> the signal calculated predicted Eb/N0 would be +3.5 dB,
> and I got a decode at +3.8 dB.
>
> A distance record for message decode at the 67km band.
>
> Bielefeld: Eb/N0 +13dB, *Decoded*
>
> Warsaw: Eb/N0 -10.7 dB;
>
> Cumiana: Eb/N0 +5.0 dB *Decoded*
>
> First message decode Germany to Italy at this band.
>
> A nice result for first use of 16K23A.   Decoder needs 3.5 Gbyte
> RAM for this message size with optimum list length.
>
> --
> Paul Nicholson
> --