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Thursday, March 11, 2021

CONTINUITY: Building a Vacuum Tube Computer: Four-Bit Instruction Register

This project's goal is to build a vacuum tube implementation of the Motorola MC14500B Industrial Control Unit, a CMOS microcontroller with a one bit data path which was manufactured between 1977 and 1995 and frequently used to replace electromagnetic relay controllers in industrial equipment.

The electrical design is interesting, using a B+ voltage of just 24 volts, which is great for safety and avoiding unwanted excitement, but limits the fan-out of gates.

Posted at March 11, 2021 15:51