Using 4 operational amplifiers this circuit generates 4 different tones. The circuit is from an American documentation from the 90's. Operational amplifiers are tTL084.
The name of this effect obtained in a 1985 documentation is due to the way the lamps light up in...
Found in an issue of Elektor magazine in the 90s, this battery tester is based on the LM3914. The...
This circuit, found in similar versions in other articles in this section, dynamically tests...