This circuit appeared in Radio Elecronics magazine in 1968. The operating circuit is a general-purpose type at the time and the power supply must be symmetrical.
We have other similar setups on this site. This one is from September 1976 Radio Electronics. The...
This low voltage AC control uses a triac. Any TIC series triac can be used and this device must be...
Using germanium transistors, this amplifier provides a 540mW output power when powered by 9V. We...