This circuit was found in an American documentation from 1975. The components of the time can no longer be found easily, but they can be tested equivalent.
We found this active crossover in a Radio Electronics magazine from June 1961. Note the different...
Found in Popular Electronics from the 90s, this circuit serves to indicate the output level of a...
If you are on an old PC that you use for experiments, control or other applications, this circuit is...