This circuit can be used as a lockable shield. A pulse activates the relay that remains on even after the pulse disappears. The transistor is general purpose.
This simple NiCad battery charger was found in an English documentation. Resistors R2 and R3...
This traditional stable configuration with the TTL 7400 integrated circuit was obtained in a...
This circuit uses two sensors that are placed at the intersection of a miniature railroad, causing the LED...