Did Early Computers Ever Use Vacuum Tubes the Size of Light Bulbs?

💡 The Answer

• Yes, machines like ENIAC used over 17,000 vacuum tubes, each roughly the size of a standard bulb.
• These tubes generated immense heat and frequently burned out, requiring constant replacement.
• The ENIAC consumed about 150 kilowatts of power, enough to dim lights in nearby buildings.
• Moving from tubes to transistors in the 1950s drastically reduced size, heat, and power use.
• Some tubes were actually larger, like the 6AS7G, used in early memory circuits.