We found this circuit in the October 1980 issue of Radio Electronics magazine. The circuit uses general-purpose transistors driving a relay.
We found this circuit in a Mullard manual from 1960. The transistor is a phototransistor of the...
The circuit that gave rise to this configuration was found in a magazine of the 1980s with the...
This oscillator with FET was found in Popular Electronics from the 90s. This traditional...