Found in old documentation, this source uses an integrated circuit from that time, which is uncommon nowadays. The power source has a ripple below 1 mV.
In this circuit the LED lights up when the input voltage drops below the value set in the trimpot. The...
The critical components of this project from a 1978 publication are the transformers, which can be...
This is a circuit that should not be used for readers interested in a fair game. The circuit...