This circuit for controlling high power LEDs (up to 2A) is from a General Electric documentation from 1970. The circuit serves to modulate a transmitter in PWM. The circuit serves as a shield.
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...