This circuit produces a pulse when the voltage in the regulator exceeds a certain value depending on the components. PUT is not a common component today. The circuit is from a 1970 EEE.
This low voltage lamp flasher can be powered from 12 V supplies. Frequency is adjusted by P1 and...
The transistors in this circuit, found in an American publication in 1975, can be replaced by...
This circuit, from an old publication, can also use modern transistors. Note that the unit is...