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.
This circuit consists of a Step-Down converter (voltage reducer) that can provide a 5 A output with...
This circuit produces a IR beam with a frequency adjusted by the 100k pot. The circuit can be used in...
This simple current control setup was found in documentation from the 60's. The low current...