Found in a Popular Electronics from the 1990s, this circuit monitors the voltage of a power supply or battery. The trigger voltage is adjusted with a potentiometer.
This ultra-low distortion driver was found in 80's Analog Devices documentation. The circuit has a...
This second-order filter was found in a documentation from the 90's. It can be implemented with...
This circuit goes into operation producing a sound on a small speaker when the supply voltage...