This circuit is used to protect an amplifier from excessive power output that would cause problems for the speakers. The circuit is from the January 1985 issue of Radio Electronics magazine.
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...