Found in an Elektor from the 90s, this circuit is suitable for viewing audio signals on an oscilloscope. The operational amplifier admits equivalent.
In the figure we have the simple way to obtain a digital inverter using a general-purpose...
This circuit works with only 1.5 V and can be powered by a solar panel. The circuit is from 1991....
This circuit was found in a 1969 EEE. The circuit uses transistors from the era that can be...