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.
We found this circuit in a technical documentation from the 70s. It can be implemented with more...
We found this shield circuit in a 1991 technical documentation. The phototransistor can be...
This circuit was obtained from a Radio Electronics from October 1963. The 4 transistors must be...