This dual-LED circuit indicates three signal levels. It was found in the January 1996 issue of Electronics Now magazine. The integrated circuit may be an LM339 or another comparator.
The presented circuit uses an operational amplifier that is uncommon nowadays, but it can be...
This circuit was obtained in an English magazine from 1978. We can easily assemble it because all...
This configuration similar to many of this site was found in 1965 General Electric documentation. Modern...