This high impedance circuit was found in 1967 documentation by Ferranti. The original operational amplifier is from that time. The circuit can be implemented with modern equivalents.
In the figure we have the diagram of an amplifier stage using transistor and a 6AQ5 valve. The...
Being able to operate with frequencies up to 100 kHz, this circuit was found in a 90’s...
This circuit immobilizes a car with an old ignition system with platinum switches. It was found in the...