A Blast from the Past on a Wall Panel

A retired UK-based enthusiast, known simply as Mike, has captivated the tech community with his ambitious DIY project: an 8-bit computer constructed entirely from 460 recycled vacuum tubes. Mounted on a large 190 x 130 cm acrylic panel fixed to a brick wall, this machine is not just a visual spectacle but a functional piece of engineering history.

The system utilizes 920 triodes housed within 460 Soviet-era 6N3P double triodes. Each tube is configured as an identical NOR gate, a design philosophy similar to that found in the historic Apollo Guidance Computer. The setup includes registers, counters, an 8-bit arithmetic logic unit (ALU), and a ring-oscillator clock, all distributed across 46 plug-in boards.


Engineering for Performance and Safety

Despite its complex appearance, the computer operates with a clear, intentional simplicity. The instruction set supports 16 operations, and while it lacks a traditional pipeline, it is capable of chained arithmetic operations ranging from 16-bit up to 128-bit. To keep the project manageable and safer, Mike maintains the high-tension power supply below 100V.

This design choice offers several benefits:

  • Allows for a compact layout with components spaced just 2 mm apart.
  • Creates a cleaner, minimalist aesthetic.
  • Ensures the hardware is relatively safe to touch, even while hot.

The Sensory Experience and Future Goals

The machine is currently being refined to run a custom-coded flight simulator, utilizing ex-British Rail flip-digit displays to show output. Beyond its technical capabilities, the computer provides a distinct sensory experience. As Mike notes, after the device warms up, the room fills with a unique scent:

«The room fills with the smell of hundreds of double triodes burning off their dust, which creates a pleasant homely aroma.»

However, the journey has not been without its challenges. The tinkerer has reported that previous versions of the build have suffered from explosive failures. While early incidents caused panic, they have since become part of the experience, with his wife even gifting him a fire extinguisher as a practical precaution. Despite the occasional loud "BANG," Mike remains fully committed to finalizing his vintage-inspired computational marvel.