Found in American documentation from the 1990s, this circuit has active cycle control. The basic components are given along with the diagram. Transistors are general purpose.
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...