This circuit is one of many of its kind that can be found on this site. This one is from a September 1987 Radio Electronics. The triac must be controlled according to the load.
An article in Radio Electronics magazine from November 1962 taught how to connect two common...
In the figure we have the way to use the transistors of an old-paired pair as a trigger circuit. The...
This amplifier is from Motorola documentation from the 70s. The circuit uses transistors from the...