This circuit was found in an Electronics World of 1968. The transistor can be any general purpose and the double T must be set to R3 for the desired effect.
We found this circuit with a Q factor of 25 in the Linear Applications Handbook by National...
This circuit was found in a Japanese publication from 1971. The circuit uses components from the...
When this circuit is activated the LED flashes for a moment indicating that the function has been...