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
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