This circuit from Ferranti was released in 1969. It makes use of the company's transistors that admit current equivalents. The input voltage is 30 mV for total deflection. The band pass is 800 kHz.
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...