This circuit was obtained in an Electronic Engineering of the 90s. The operational amplifiers and the sensor are from that time. The circuit has symmetrical power supply.
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...