We found this circuit in the National Semiconductor's Linear Applications Handbook of 1994. The circuit uses an operational transconductance amplifier.
This configuration was found in a 1990s documentation. Modern operational amplifiers can be used...
Found in a 1960 Gernsback documentation, this circuit triggers an electromechanical counter of the...
This powerful amplifier was part of commercial sound circuits from the 90s. The integrated circuit...