This circuit of a Popular Electronics from the 90s makes use of components of the time. The circuit has sampling and retention capabilities and a conversion rate of 1V / kHz.
This circuit was originally suggested in a 1968 publication to generate a white mark (frame) on a...
This CMOS circuit was found in the July 1990 Radio Electronics magazine. Power is for a 12V...
This is the traditional configuration of an AND gate using an operational amplifier. Operational...