Re: LF: WSPRX_08r3575

[Stefan Schäfer <Stefan.Schaefer@iup.uni-heidelberg.de>]

Yes, CFM...

Am 03.10.2013 21:13, schrieb Graham:
> The  software  reported  2 dB  change  ?
>
> --------------------------------------------------
> From: "Stefan Schäfer" <Stefan.Schaefer@iup.uni-heidelberg.de>
> Sent: Thursday, October 03, 2013 8:08 PM
> To: <rsgb_lf_group@blacksheep.org>
> Subject: Re: LF: WSPRX_08r3575
>
> > G
> >
> > 4X1RF and GW0EZY took a recording of my WSPR transmission and sent it 
> > to me via dropbox, a wav file recorded in SpecLab.
> > I run the recordings in an endless loop and produced a set of 
> > decodes, 5 decodes for each setting, just to make sure that there is 
> > no random difference in the S/N shown for the same settings. Mostly 
> > the S/N shown was the same for a certain setting, maybe 1 of 5 
> > differed by 1 dB. The results were quite clear. I've done the test 
> > with strong signals (GW0EZY) and weak signals (4X1RF). There average 
> > improvement was 2 dB, maybe a bit more.
> > 73, Stefan
> >
> > Am 03.10.2013 20:45, schrieb Graham:
> > > How did  you  measure the  2 dB  Stefan ?
> > >
> > > --------------------------------------------------
> > > From: "Stefan Schäfer" <Stefan.Schaefer@iup.uni-heidelberg.de>
> > > Sent: Thursday, October 03, 2013 6:47 PM
> > > To: <rsgb_lf_group@blacksheep.org>
> > > Subject: Re: LF: WSPRX_08r3575
> > >
> > > > Hi Tobias,
> > > >
> > > > Am 02.10.2013 16:19, schrieb Tobias DG3LV:
> > > > > Hi Stefan/LF !
> > > > >
> > > > > Information on the SVN-server says, that there was a noise blanker 
> > > > > added.
> > > > Thanks for all the infos.
> > > > Finally :-) During the time he developed WSPR-15 we were in regular 
> > > > email contact. To that time i made some tests with DF6NM's slow 
> > > > WSPR version, tests with 4X1RF and GW0EZY and others. We found that 
> > > > the SpecLab noise blanker in front of the WSPR input (using VAC) 
> > > > made a S/N improvement of at least 2 dB. Obviously he anyway didn't 
> > > > include such a tool (which is much more useful on LF/MF as on the 
> > > > HF bands i think) in the previous versions.
> > > > Now the question is if the new intenal NB is more efficient than an 
> > > > external SpecLab NB. One could do a test running 4 WSPR-x 
> > > > instances, the old one, with and without a SpecLab NB and then the 
> > > > new one, with and without a SpecLab NB... If the new one without a 
> > > > SpecLab NB performs best, then this would be really an improvement 
> > > > over the older version! If i can find the time i will do such a 
> > > > test at night.
> > > > 73, Stefan/DK7FC