Topband: SDR/DSP pulls out signals HOW FAR down in the noise?

[Mike Waters W0BTU]

Hello Topbanders,

Has anyone used DSP and/or and SDR to receive extremely weak signals on 160 that 
are buried in the noise? 


I posted an inquiry about how DSP might pull out signals buried in the noise 
that are "impossible"  to copy even with a good ear/brain combo. I've done quite 
a bit of Googling. However, the only real 'hard evidence' I've seen is at 
http://www.sdrham.com/winrad/index.html .  Go to the bottom of the page, where 
it says:

"As an example of the filtering features, listen to these two audio samples.
>In the first, a CW CQ EME is made completely inaudible by static crashes.
>The second sample is the same audio file, but filtered trough the Noise Blanker 
>feature of Winrad."
>
>Listen to the two audio files. It is simply amazing.
>I'm not calling that site author a liar. Nothing like that. I just want to hear 
>from others who can say they see that same enhancement regularly, and under what 
>set of circumstances.

If anyone is so inclined, I'd appreciate your opinion on a related inquiry I 
posted at

http://www.eham.net/ehamforum/smf/index.php/topic,72452.0.html
and
http://forums.qrz.com/showthread.php?t=276972

Interesting subject. At least I think so. Regardless of what people say in 
reply, I'd like to try this myself. But I'd rather not re-invent the wheel, 
which is the reason for my post.

At  the very least, perhaps all it would take is connecting RX audio to a good 
sound card on a PC running the right software. Or, the RX IF to an SDR which is 
in turn connected to a good sound card (as ON4UN mentions in his new book).

 73,
Mike Waters
www.w0btu.com