Found in a 1947 publication, this 7-tube amplifier uses four tubes in the output stage. The circuit uses a power source with a transformer.
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...