The circuit is from an Electronics Hobbyst Handbook from the 90s, being valid for panels of the time, with lower performance. The circuit supplies 2.4V with 125mA current.
This circuit warns when the headlight bulb is on. We found it in a Popular Electronics from the...
The oscillator shown in the figure keeps its frequency constant in an active cycle adjustment...
This circuit was found in an Argentine publication from the 1970s. The circuit can be assembled with...