Circuits for the FX-1 computer

Abstract

A set of computer logic circuits capable of 50-megapulse operation is described. Included are gated and mixing pulse amplifiers, a static flip-flop, a diode logic unit with current-steering amplifier, a passive delay line, and an active variable delay circuit, all of which are designed to operate with terminated 75-ohm transmission lines. Ten-nanosecond pulses and 20-nanosecond flip-flop transition times are achieved through use of very-high-speed MADT transistors. The circuits have been successfully employed in the FX-1, a small general purpose computer with a high-speed magnetic-film memory.