This circuit was found in a 90s Electronic Engineering. The quadruple operational amplifier can be replaced by an equivalent. RL determines the tested resistance range.
This analog volt-ammeter was found in an Electronics World of 1968. It makes use of a 0-1 mA...
This circuit was found in an Electronics Now. Its purpose is to generate clock pulses for a...
Found in a 1969 documentation on neon lamps, it actually takes advantage of the durability of the neon...