In the figure we have the way to implement a logic gate or (OR) with an LM393. The circuit must be powered by a symmetrical source and other operational ones can be used.
Found in Popular Electronics from the 1980s, this circuit can use more modern transistors such as...
This circuit is from a Radio Electronics from February 1970. The integrated circuit is an...
This is stage is transformer coupled and was found in na old publication of the year 1958. The...