autonomous singers

i want to introduce two new autonomous circuits i have built and added to my e-beastiary. the circuits are variations based on the solarsoundmodul by Ralf Schreiber. the critters are photovoric singers that employ a Schmitt Hex Inverter IC, resistors, capacitors, piezo buzzers, and a photovoltaic cell. the modulation is slightly different on each output pin from the varied combination of capacitance and resistance. they range from creaking to screaming, lilting to terse. more…