[Lf] [Fwd: LF: Re: QRSS question]

[Andre' Kesteloot]

Alberto di Bene wrote:

> Andrew Talbot wrote:
>
> > How about letting it go slow enough for a 30s dot  or a resolution bandwidth
> > of 0.01Hz - as far as I know the only soundcard software that could get
> > anywhere near this and do proper SLOWCW was Spectran.
> >
> > None of this fast 3s dot stuff !    My 56002 EVM system can get down to 1
> > hour dot intervals, looking in a bandwidth of 100 uHz (micro Hz).   That
> > would span the Altantic with 1mW ERP if present records are anything to go
> > by.   Pitgy it would take several days for a proper QSO !!!!!!!   :-(
> >
> > Andy  G4JNT
> >
>
> Andy,
>             thanks for the suggestion, which I have implemented this evening.
> Summing up, at present the supported modes are :
> - Full Band View, a span of 1.5 kHz
> -   3 sec/dot, the screen is refreshed 5 times per second, with 0.34 Hz resolution.
> - 10 sec/dot, the screen is refreshed 2 times per second, with 0.08 Hz resolution.
> - 30 sec/dot, the screen is refreshed every 1.5 seconds,  with 0.021 Hz resolution.
>
> About your micro Hz resolution, it can be done also with a PC, the fastest
> Pentiums nowadays process a FFT butterfly in a shorter time than the 56002 DSP.
> But, as you rightly pointed out, the problem lies in that reciprocal relationship between
> F and T .....
>
> 73
> Alberto   I2PHD