Found in a 1969 Burr-Brown publication, this circuit makes use of integrated components from that period. With modern equivalents, it can be adapted to be used as a shield.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...