This circuit was found in the August 1993 Electronics Now magazine. It is for telephones used on common old-style analog lines.
Found in RCA documentation two years 70, this circuit triggers an incandescent lamp at dusk. The...
Found in Popular Electronics from the 90s, this circuit is based on a PLL567 and employs high-end or...
This circuit was obtained in an English publication of 1977. The operational is of the type with...