This circuit was obtained from an 80's EDN. The components used are still common. The circuit can be used as a shield and the frequency is approximately 775 Hz.
This circuit was found in a 2003 documentation. Its purpose is to check if the transmitter of an...
Found in old English documentation this circuit evaluates the power of a transmitter. The circuit has...
The circuit shown is suggested by National Semiconductor's Linear Applications Handbook. The base...