>Digisound had one called the "Waveform Multiplier."
I have been meaning to do this one for quite a while after Chris
Crosskey (Atari madman and generally nice bloke) told me about it. It
should be easy enough to do, although the Digisound's PCBs set up was
horribly complex with all the little daughter boards. I tried the basic
principle and it certainly does work. If I get around to it, expect it
sometime in the Summer.
Regards,
Tony Allgood Penrith, Cumbria, England
Oakley Sound Systems www.oakleysound.com