Re: LF: NA VLF

[Markus Vester <markusvester@aol.com>]

D'oh, pity! That message sounded so plausible, and at 0.5 dB EbN0 I wasn't suspecting a false decode.

Joe, could you perhaps remind me of your EbNaut timing parameters again? I seem to have missed an email mentioning them.

I don't think that mutual QRM would have been much of a problem. The two signals would be perfectly orthogonal if you used identical symbol timing and chose a carrier frequency spacing which is a multiple of the inverse symbol period (i.e. 0.05 or 0.1 Hz for Stefan's 20 s symbols). 

Best 73,
Markus
 


-----Ursprüngliche Mitteilung-----
Von: jcraig <jcraig@mun.ca>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Di, 23. Mai 2017 17:12
Betreff: Re: LF: NA VLF

Paul and Markus,

Thank-you for the encouragement and patience, but infortunately the
message received does not match the one that was sent, assuminmg the
sending was done correctly. Can we try again?

Hopefully I am not causing QRM to Stefan's QTC on 8270.1 Hz. If so I can
QSY back to 8277 Hz! Can we try his suggestion for a daytime attempt to
take advantage of the lower QRN or will the S/N be too low?

Also, are the sigs stable enough? Stefan suggested a GPS module that
could be used with Spec Lab to generate a disciplined carrier. The WX
should be more stable now. Last night the ERP decreased and the phase
probably shifted too.

73
Joe VO1NA

On Tue, 23 May 2017, Markus Vester wrote:

> Paul and Joe,
>
> great news! Your patience has finally paid off. Congratulations to both on this excellent piece of work!
>
> 73,
> Markus (DF6NM)
>
> -----Ursprüngliche Mitteilung-----
> Von: Paul Nicholson <vlf0403@abelian.org>
> An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
> Verschickt: Di, 23. Mai 2017 12:07
> Betreff: Re: LF: NA VLF
>
>
>
> Overnight 22nd/23rd was fairly quiet and the decoder turned up
>
> 'VO!'
>
> at Eb/N0 = +0.5dB, BER 42.7% with constant reference phase,
> peaking at frequency of 8270.0070925 Hz + 6 uHz.
>
> Rank 7430 in the decoder list.
> Carrier S/N: 12.81 dB in 39.2 uHz,
> -31.26 dB in 1Hz,
> -65.24 dB in 2.5kHz
>
> --
> Paul Nicholson
> --