Abstract
Regulated metallic rectifiers have been used throughout the Bell System to provide talking current, to power relays, switches, and vacuum-tube filaments; and to supply vacuum-tube plate potentials. With the advent of semiconductor devices such as transistors and junction diodes, the regulated metallic rectifier is assuming added importance. However, the lower voltages generally required by these semiconductor amplifier and switching devices have required a re-evaluation of the regulating principles used in metallic rectifiers. It has been found possible to replace previous vacuum-tube and magnetic-amplifier regulating circuits with equivalent and usually more compact and efficient semiconductor apparatus. This paper discusses the suitability of silicon-alloy junction diodes having very sharp reverse breakdown characteristics in the reference standard portion of closed-loop feedback regulating circuits of metallic rectifiers.