This peak detector has a memory to prolong the response. The circuit is from American documentation from the 1980s. The supply does not have to be symmetrical.
We found this circuit in a Popular Electronics of the 90s. Its purpose is to detect when it locks...
This circuit controls the passage of the signal from one speaker to another. The potentiometers must be of...
Obtained from a 1969 documentation, this circuit can operate at frequencies up to 500 Hz, counting up...