Extract Fumes In Midcentury Style With Nixie Tubes And Military Surplus

Nobody wants to breathe solder fumes; that’s a given. For most of us, an industrial-looking fan-and-filter made in China and picked up cheap feels like more than enough to keep our lungs clear. Other people, people like [George Conneely], have more refined tastes. Why have a fume extractor when you can have a work of art?

The insides aren’t quite as pretty as the outside, but it’s a clean build.

This is one of those projects where the images really speak for themselves, because the whole point is to be beautiful. Sure, the wooden case is lovingly sculpted by a—wait, it’s 3D-printed!? Yes, with the right stain and care applying it, it seems Wood PLA can fool the eye, or at least the camera. Inside that PLA case there’s a custom PCB with an ATMega microcontroller and some MOSFETS to drive the Nixie tubes. The two digits represent the fan’s set RPM as a percentage of maximum, as is clearly labeled. Using a READY/NOT READY indicator pulled from a Panvia Tornado to show whether the fan has actually spun up to its set speed is an amazing touch.

The only problem with this build is that it is too nice. We’d almost rather see it on Don Draper’s desk than risk dirtying it on a lab bench. Evidently, [George] ascribes to the philosophy that one should surround oneself with beauty whenever possible. Your tastes may differ, but to many, nixie tubes certainly qualify– whether on a desk clock or in a car’s dashboard, there’s just something about that incandescent glow.

Thanks to [George] for the tip.

Salvaged VFDs In Nixie-Like Clock

In between the Nixie tube era of the 50s and 60s and the advent of multi-digit vacuum fluorescent displays (VFDs) common in 80s and 90s consumer technology, there was a brief time in the early 70s where single-digit VFDs were commonplace. Superficially these devices look like Nixie tubes, but have a number of advantages to them including lower voltage, lower power requirements, and lower cost. [maurycyz] recently found a number of these salvaged from old calculators and used them to build a retro-themed clock.

[maurycyz] was not able to find datasheets for this display, but was able to reverse-engineer each of the digits. Similar to vacuum tubes there is a heater which has a few ohms of resistance, and from there each of the segments of the digit can be deduced by probing the 13 signal wires. These are analog devices in some respects, so a lot of experimentation had to go into driving the displays to find their optimal conditions. A quartz crystal was used for timekeeping with an AVR128DA28 microcontroller chosen to provide control for the digits, using seven pins as segment drivers and four as grid drivers. Each digit uses around 0.14 watts, so with all four digits on it can consume a little over half a watt. A simple wood enclosure rounds out the build.

As Nixie supply wears thin, VFDs like this can be an excellent stopgap or replacement while still building retro-themed displays like this clock or this calculator which uses similar VFDs for each digit.

Nixie Gear Indicator Shines Bright

When you’re driving a car with a stickshift, it’s pretty easy to keep track of which gear you’re in. That can be a little bit more difficult on something like a motorcycle with a sequential shifter. [decogabry] built a neat gearshift indicator to solve this issue.

An ESP32 devboard is used as the brain of the build. It’s paired with an ELM327 dongle over Bluetooth, which is able to hook into the bike’s ODB diagnostic port to pick up data like engine RPM, wheel speed, and coolant temperature. The first two factors are combined in order to calculate the current gear, since the ratio between engine RPM and wheel speed is determined directly by the gear selection. The ESP32 then commands a Philips ZM1020 Nixie tube to display the gear, driving it via a small nest of MPSA42 transistors. A separate self-contained power supply module is used to take the bike’s 12 volt supply up to the 170 volts needed to run the tube. There is also a small four-digit display used to show status information, RPM, and engine temperature.

Notably,  [decogabry] made this build rather flexible, to suit any bike it might be installed upon. The gear ratios are not hard coded in software. Instead, there is a simple learning routine that runs the first time the system is powered up, which compares RPM and wheel speed during a steady-state ride and saves the ratios to flash.

We’ve featured projects before that used different techniques to achieve similar ends. It’s also interesting to speculate as to whether there’s a motorcycle vintage enough to suit a Nixie display while still having an ODB interface on board as standard. Meanwhile, if you’re cooking up your own neat automotive builds, don’t hesitate to drop us a line.

Nixie Tube Dashboard Is Period-Appropriate Hack To Vintage Volvo

There’s no accounting for taste, but it’s hard to argue with The Autopian when they declare that this Nixie tube dash by [David Forbes] is “the coolest speedometer of all time” — well, except to quibble that it’s also the coolest tachometer, temperature gauge, oil pressure indicator, and voltmeter. Yeah, the whole instrument cluster is on [David]’s Volvo PV544 is nixified, and we’re here for it.

He’s using a mixture of tubes here– the big ones in the middle are the speedo and tachometer, while the ovals on either side handle the rest. There’s a microcontroller on the front of the firewall that acts a bit like a modern engine control unit (ECU) — at least for the gauges; it sounds like the Volvo’s engine is stock, and that means carbureted for a car of that vintage.

The idea that this hack could have been done back in the 50s when the car was new just tickles us pink. Though you’d have probably needed enough valves to fill up the boot, as our British friends would say. Translate that to “enough vacuum tubes to fill the trunk” if you’re in one of the rebellious colonies.

We’ve featured [David]’s projects previously, in the form of his wearable video coat. But his best known work is arguably the Nixie Watch, famously the timepiece of choice for Steve Wozniak.

Thanks to [JohnU] for the tip!


All images by Griffin Riley via The Autopian

This Soviet-Style Clock Uses Homemade Nixie Tubes And Glowing Logic

The Neon glow of a Nixie tube makes for an attractive clock, but that’s not enough neon for some people. [Changliang Li] is apparently one of those people, because he’s using soviet-era cold-cathode tubes as the logic for his “Soviet-Era Style Clock”

Aside from the nixies for display, the key component you see working in this beautiful machine are the MTX-90 cold cathode thyratrons, which look rather like neon tubes in action. That’s because they essentially are, just with an extra trigger electrode (that this circuit doesn’t use). The neon tubes are combined into a loop counter, which translates the 50 Hz mains circuit in to seconds, minutes, and hours. The circuit is not original to this project, and indeed was once common to electronics books. The version used in this project is credited to [PA3FWM].

The Nixie tubes are new-made by [Sadudu] of iNixie labs, and we get a fascinating look in how they are made. (Tubemaking starts at around 1:37 in the video below.) It looks like a fiber laser is used to cut out glow elements for the tube, which is then encapsulated on a device which appears to be based around a lathe.

The cold-cathode tubes used as logic rely on ambient light or background radiation to start reliably, since the trigger electrode is left floating. In order to ensure reliable switching from the thyratrons, [Changliang Li] includes a surplus smoke detector source to ensure sufficient ionization. (The video seems to imply the MTX-90 was seeded with radioisotopes that have since decayed, but we could find no evidence for this claim. Comment if you know more.)

The end result is attractive and rather hypnotic. (Jump to 3:37 to see the clock in action.) If you want to know more about this sort of use for neon lamps (and the Soviet MTX-90) we featured a deeper dive a while back.

Thanks to [Changliang Li] for the incandescent tip. If one of your bright ideas has had a glow up into a project, don’t hesitate to share it on our tips line.

Continue reading “This Soviet-Style Clock Uses Homemade Nixie Tubes And Glowing Logic”

2025 One Hertz Challenge: The Easy Way To Make A Nixie Tube Clock

Let’s say you want to build a Nixie clock. You could go out and find some tubes, source a good power supply design, start whipping up a PCB, and working on a custom enclosure. Or, you could skip all that, and just follow [Simon]’s example instead.

The trick to building a Nixie clock fast is quite simple — just get yourself a frequency counter that uses Nixie tubes for the display. [Simon] sourced a great example from American Machine and Foundry, also known as AMF, the company most commonly associated with America’s love of bowling.

The frequency counter does one thing, it counts the number of pulses in a second. Thus, if you squirt the right number of pulses to represent the time — say, 173118 pulses to represent 5:31 PM and 18 seconds — the frequency counter effectively becomes a clock. To achieve this, [Simon] just hooked an ESP32 up to the frequency counter and programmed it to get the current time from an NTP time server. It then spits out a certain number of pulses every second corresponding to the current time. The frequency counter displays the count… and there you have your Nixie clock!

It’s quick, dirty, and effective, and a sweet entry to our 2025 One Hertz Challenge. We’ve had some other great entries, too, like this nifty hexadecimal Unix clock, and even some non-horological projects, too!

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Close up of a DA14 nixie multimeter

The Nixie Tube Multimeter That Almost Made A Comeback

In a world of digital monotony, the Avo DA14 digital multimeter, with its vintage nixie tube charm, is a refreshing gem. Recently refurbished by [Thomas Scherrer], this multimeter video review is a blend of nostalgia and tech savvy. The DA14 not only has style, but substance — delivering resistance, current, and voltage measurements that make you wonder why more multimeters didn’t stick with this stylish glow.

As [Thomas] starts by powering up the DA14, we were instantly captivated as the Nixie tubes illuminate in their retro orange. With each twist of the dial, he demonstrates just how intuitive the multimeter is to operate, walking us viewers through each function while giving some extra love to its calibration process—a neat front-panel potentiometer that requires just a touch of finesse to get perfect readings.

But, as with all good tinkering tales, things go downhill when issues with analog inputs and the display pop up. A teardown reveals a beautifully complex inner assembly of transformers, rectifiers, and circuit boards, giving the DA14 its impressive yet fragile structure. When the critical defective display chip is found, hopes for a full repair dim. His story ends without a revival, but if you want to see a similar attempt that did get resurrected – albeit without those nixie digits – take a look at this LCD transplant we covered previously.

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