TB303 vco

[Tony Allgood]

Hi,

I tried to simulate the TB vco today. Couldn't get the blasted thing to
oscillate. The expo worked fine but that SCR is too dependant on
parasitics and leakages to simulate properly on my machine. Mind you I
am not using spice, maybe the models in this would be better. I am using
the mixed mode sim in EDWin and to be honest I don't fully understand
some of the parameters that EDWin allows me to change. I never really
paid attention in my Physics of Semiconductors classes, and it was a
long time ago. I may have a go at building a real one to find out whats
really going on. I think it is quite an elegant VCO design in its almost
brutal and simplistic approach.

Regards,

Tony Allgood, Cumbria, UK

e-mail: oakley at techrepairs.freeserve.co.uk

Rack mounted Moog VCF module. Details to be found at...

http://aupe.phys.andrews.edu/diy_archive/schematics/effects/filter.html