Capacitance multiplier (CB7803E)

We found this circuit in an old Popular Electronics. The circuit can be applied to other operational amplifiers.

Fast logarithmic converter (CB9613E)
Found in old documentation, this circuit makes use of amplifiers of the time, uncommon today. Next...
Rumble Filter with LM381 (CB25279E)
Rumble is a low-frequency oscillation that occurs in turntables due to variations in motor speed....
Stair signal generator (CB9144E)
This circuit was found in a Popular Electronics from the 90s. The circuit uses common components...