functioning prototype of my muscle stimulation device.
I am generating short 100Hz square-wave pulse trains (0.5 sec long) in super-collider and outputting them via my headphone jack. The circuits are a power amplifier and then signal-transformers in reverse as voltage step-up devices.
Circuit diagrams here http://svn.roberttwomey.com/eagle/estim and http://svn.roberttwomey.com/eagle/ampboard. The power amplifier in this video is a temporary LM386 based circuit (built with RadioShack(tm) parts) until my surface mount components arrive.
Fancy PCB milled on LPKF circuit mill Protomat S100.
the transformers are the only expensive part. And the electrodes I purchased on amazon. I don't know, maybe $40 all together. Plus time to make the boards.
rtwomey 6 months ago