Found in an 1989 R-E Experimenters Handbook, this circuit produces several sound effects that can be modified. The signal must be applied to an external amplifier.
This circuit adds an amplifying transistor that can supply loads of up to 250 mA. The circuit is...
This circuit was found in a 1968’s publication and uses germanium transistors. The characteristic...
This circuit was found in Philips documentation from 1967. The phototransistor is from that time,...