The Tube Computer
Vacuum Tubes require high voltages to work efficiently and are not for the faint hearted. They can switch several hundred million times a second, and in the 1950s they were combined with germanium diodes as the basis for many incredible computer designs.
The Tube Computer has a modern 8 bit architecture. It is designed to run a simple airship flight sim, flying around Brighton for the grandchildren, or a 64 bit Fibonacci sequence for the grown ups.
Building tube computers has become an addiction, this is my third! The first ran on 28th May 2021 whist perched on our dining room table, chairs and surrounding floor space. A fairly harmless addiction, I suppose!
After switch on you have to wait a while for the vacuum tubes to warm up. If you look from the side you see them start to show a red glow. After about a minute The Tube Computer has a pleasant homely aroma from the hundreds of double triodes, all quietly burning off their dust.
The Tube Computer is still a work in progress, and live adjustments are often required. It takes about 10 minutes to thermally stabilise, then a last few tweeks, check the fire extinguisher is full, and run the software.
