This circuit turns off a load after an interval of 8 to 80 seconds adjusted on the potentiometer. The circuit is from a Radio Electronics June 1970. The time depends on C1 and can be changed.
This simple radio was found in a Popular Electronics from the 90s. L1 and L2 have 100 turns on a...
This circuit was found in Radio Electronics magazine from the 90's. The circuit is for small NiCad...
This automotive circuit was obtained from an 80's schematic from the integrated circuit factory...