Found in Ferranti's 1968 documentation, this circuit uses a Darlington photo transistor to drive a 12V relay. The circuit can be implemented with modern equivalent components.
November 2016 - Mouser Electronics is indicating in its inventories the new NXP Kinetis L MCUs....
We found this circuit with an operational transconductance amplifier in the Motorola Linear...
This circuit for a receiver was found in an English documentation from 1963. The transistor is made of...