Found in an American publication from 1969, this circuit can be adapted to be used as a shield. Operational amplifiers can be of modern equivalent types.
We found this circuit in a technical documentation from the 70's. Any double-gate MOSFET can be...
In this circuit the LED lights up when the input voltage exceeds the value set in the trimpot. The circuit...
This oscillator with emitter follower was found in an American documentation from the 80's. The...