Maybe you are looking for something like this?
http://www.winradio.com/home/g303-demod.htm

On 21 Apr 2004 11:08:22 -0700, (Yan) wrote:

Hello,

how do I decode sideband signals using my PC ? I want some DSP based
BFO or some filter...

I have been looking at many software but none seem to offer this
functionnality.

Thanks !