This circuit was obtained in an Electronics World of 1968. The operational amplifiers ones are types of the time, no longer used today. The circuit responds from less than 20 Hz.
This detector circuit was found in documentation from the 1980s. The diode is a high frequency detector...
This circuit was found in an American documentation from the 90's. The circuit is intended for...
Found in American documentation from the 90s, this circuit can be implemented with modern...