Message-ID: <3A4BE735.A97EEC6E@usa.net>
Date: Fri, 29 Dec 2000 02:21:57 +0100
From: "Alberto di Bene" <dibene@usa.net>
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To: rsgb_lf_group@blacksheep.org
Subject: LF: Re: QRSS question
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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