This circuit is from a Popular Electronics from the 90's. The audio amplifier admits equivalent. The others integrated are not very common today.
This circuit is from a 1968 Electronic Design. The components are from the era and the operating...
In this charger the current is limited by the incandescent lamp. Lamps from 40 to 100 W can be...
This circuit was presented in a January 1990 Radio Electronics magazine article as part of a home...