This sophisticated moving bar indicator circuit with the LM3915 is from a Radio Electronics magazine from May 1985. The two-channel circuit includes the power supply.
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...