This configuration that appears in other points of this section was obtained in a 90’s Popular Electronics. The circuit can be applied to other operational ones.
This circuit has an output that provides the average value of the rectified voltage. Operational...
This circuit reproduces the dial noise in a small speaker. The transistor can be a general-purpose type....
Suggested by Siliconix in 1980s documentation, this circuit uses currently uncommon components. The...