From the MAKE Flickr pool
The nixie tube isn’t the only vintage tube display device – The Dekatron was used in computers and calculators as far back as the 1940s. Eschlaep’s put one to a bit of practical use as what is likely the coolest and highest power kitchen timer evers –
Dekatrons are relatively difficult to find, so I decided to use a single Dekatron in my timer. Actually this project is an old one that I revisited. The original project was just going to be a spinner, but I had trouble with the driving circuit (it never worked reliably). For the 2008 Maker Fair I dusted it off and tried to power it upâ€“with 12V instead of 5V. The power supply and microcontroller did not appreciate it and the whole thing stopped working. The second time around I decided to turn it into something useful.
There are twenty minutes remaining on the timer. You can read the time using the scribed lines on the brass ring around the Dekatron. The ionized gas in the tube glows purple because of the high argon content.