Found in a 1967 Electronic Design, this circuit operates in a range of 0 to 1 V input with frequencies determined by C2. The components are from the period.
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...