This circuit was found in an old manual of integrated circuits. The operational is of the time, uncommon nowadays. The power supply must be symmetrical.
Common operational amplifiers like the TL series, CA3140 and others can be used in this circuit...
This high-gain amplifier was found in the March 1994 issue of Electronics Now magazine. The...
We found this timer for times of a few minutes in a 1974 Ferranti transistor manual. The relay is 37...