An Internet Speedometer With A Dekatron

[Sprite_tm], like most of us, is fascinated with the earlier ways of counting and controlling electrons. At a hacker convention, he found an old Dekatron tube hooked up to a simple spinner circuit. The prescription for this neon infatuation was to build something with a Dekatron, but making another spinner circuit would be a shame. Instead, he decided to do something useful and ended up building an Internet Speedometer with this vintage display tube.

Like all antique tubes, the Dekatron requires about 400V to glow. After a bit of Googling, [Sprite] found a project that drives a Dekatron with an AVR with the help of a boost converter. Borrowing the idea of controlling a boost converter with a microcontroller, [Sprite] built a circuit with the Internet’s favorite Internet of Things thing – the ESP8266 – that requires only a 12 volt wall wart and a handful of parts.

Controlling the rotating glow of a Dekatron is only half of the build; this device is an Internet speedometer, too. To read out his Internet speed, [Sprite] is using a managed switch that allows SNMP to read the number of incoming and outgoing octets on a network interface. By writing a simple SNMP client for the ESP8266, the device can read how clogged the Intertubes are, both incoming and outgoing.

With an acrylic case fresh out of the laser cutter and a remarkably good job at bending acrylic with a heat gun, [Sprite] has a tiny device that tells him how much Internet he’s currently using. He has a video of it running a speedtest, you can check that video out below.

13 thoughts on “An Internet Speedometer With A Dekatron

    1. Nope, I actually mostly finished this before I went to Shanghai, but had no time to polish the code and write an article due to the move. I now have settled in a bit better so I could finish the article. I do have some interesting stuff going on at Espressif too which I’ll release in due time. (I already made an ESP8266 play MP3s on work time, for example.)

  1. Shoot… I just remembered I HAD a counter like this years ago… used a synchronous motor to spin a disk with a hole in it for timing, and it just counted in base ten. I’m now trying to figure out what the blazes I did with that thing…

  2. +1 for using SNMP ;) (I used to do a lot of snmp agent, MIB and NMS work; back when there were still companies in the US willing to pay for quality snmp mibs and agentry. now, its all offshored to india and all my years of snmp are mostly useless, now, sigh).

  3. Neat project, nice connection speed. Only one suggestion : make it spin in reverse for upload speed. This way you can see if, for example, when using some torrents, your download and upload speed are balanced (light not moving). Keep up the good work [Sprite_tm] !

    1. Problem with that is most of the time he will be uploading and downloading at the same time unless he finds top speed of upload then download and which ever is closest to 100% usage he displays that result.

      1. What I do at the moment is spin the Dekatron with a speed based on the combined upload+download speeds. If the upload speed is clearly more than the download speed, however, I’ll spin the entire thing in reverse. That way, you have info about your total speed plus if it’s mostly caused by uploading or downloading.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.