The use of a diac improves the performance of the two dimmers in the previous circuits. The circuit is from the same Radio Electronics magazine in an article that teaches how to use triacs.
This circuit came out in an American magazine that no longer exists. It's the Electronic...
This circuit originally came out in a Budget Electronics from 1981. The American magazine no...
This is the traditional audio preamp configuration with the National Semiconductor LM382. The...