This circuit keeps the neon lamp on for a moment when it receives a pulse. The turn on time depends on C. The transistor is of the old type, from the 60's, when the circuit was published.
This circuit uses a capacitor to store energy. The capacitor is charged by closing S1 by a moment. Them,...
This circuit is both a signal injector and a signal follower. A key selects the operating mode. The...
The difference between this circuit and the previous one is that it uses PNP transistors. The...