This circuit was found in a Philips documentation from 1966. Its purpose is to drive the solenoid of an electric typewriter of the time.
This simple metronome, from 1985 documentation uses only transistors and has two settings. For...
This circuit is suitable for modulating AM transmitters. The circuit is from a 1977 radio amateur...
This flasher was found in an old Hands On, but uses common components. The optocoupler can be...