The LH1605 integrated circuit is not a common component today. The circuit was found in the 1994 National Semiconductor Linear Applications Handbook.
This circuit is from the 1972 Linear Data Book of RCA, but it can be made with more modern...
I found this simple circuit from an English magazine from 1984. The circuit can be easily...
We found this logic level tester in a 1976 documentation. The circuit is powered by the voltage of the...