Found in a 1967 Ferranti documentation, this regulator makes use of an operational amplifier of the time. The output current is only 5 mA.
This circuit multiplies the input resistance of an operational amplifier. As the indicated...
This conventional flip-flop configuration with two transistors was found in documentation from the...
The input impedance of this amplifier is of the order of 1014 being the same indicated for pH...