Found in a 1980s manufacturer documentation, this circuit can be used as an optical shield. The integrated circuit is from the era and modern equivalents can be tried out.
This circuit is from an old 80's linear circuit manual. The configuration can be implemented with modern...
This detector with ultra-low deviation was found in an American documentation from the 90s....
This circuit was found in a Signetics documentation from the 1980s. Next to the figure are the...