This circuit was found in a 1968 EEE. The circuit makes use of logic gates of the time and can be tested with equivalents from modern families.
The integrated circuit used in this project is not common today, but it can be implemented with more...
Found in an American publication from 1969, this circuit can be adapted to be used as a shield....
This current meter with many scales was found in a 80s American documentation. The operational amplifier...