The transistor in this project found in the July 1994 issue of Electronics Now magazine can be any general-purpose type. The circuit is powered by the relay voltage up to 12 V.
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...