From: "Mike Dennison" <mike.dennison@ntlworld.com>
To: rsgb_lf_group@blacksheep.org
Date: Sat, 05 Mar 2005 19:20:35 -0000
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Subject: Re: LF: Re: Slow mode comparisons
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>    going from QRSS3 to QRSS10, when using Argo, means that the FFT bin
> size is 4 times
> smaller, and this results in an increase of 6 dB of SNR, provided the
> useful signal is still confined into a single bin. 
> 73  Alberto  I2PHD
> ---------------------------------

Of course. I was not suggesting there was something magical about 
slower speeds, or that QRSS10 should be used when signals are strong. 
It was just that here was a practical demonstration of the huge 
difference in readability on a signal that was just unreadable in 
QRSS3. I know the decibels - but here is what it looks like.

The downside is that the whole QSO took two hours!

Several people have defended DFCW as though I had attacked it. I was 
involved with the discussions when DFCW was first tested, and in 
suggesting some of the improvements made to it. For the record, I 
think DFCW is a very useful mode as it greatly speeds up throughput 
with similar S/N to QRSS. If you look at my pictures, though, you 
will see that on this particular occasion DFCW was slightly worse 
than QRSS.

Mike, G3XDV
http://lf.apersonalguide.co.uk
=====================