This TTL shield with high level logic is from the LM111's own 80's manual. The integrated circuit is no longer easily found, but the circuit can be adapted to use modern equivalent operational amplifiers.
This circuit was found in the November 1993 issue of Electronics Now magazine. The two-stage...
This circuit acts on a relay disconnecting the load when the input voltage exceeds the set limit....
This circuit is from a Radio Electronics from March 1970. The integrated circuit used is one of...