This circuit is from an article in Radio Electronics magazine from October 1958. The circuit is for testing electrolytics that operate at high voltages depending on the source.
We found in this American documentation this circuit for activating common cathode displays. In it we...
An application for the previous circuit (CB109) is shown here. The central frequency is determined by C and...
Indicated by a Popular Electronics of the 90s originally to measure the light determining the exposure...