Regular Hackaday readers are surely familiar with Nixie tubes: the fantastically retro cold cathode display devices that hackers have worked into all manner of devices (especially timepieces) to give them an infusion of glowing faux nostalgia. But unfortunately, Nixie displays are fairly fragile and can be tricky to drive due to their high voltage requirements. For those who might want to work with something more forgiving, a possible alternative is the Numitron that uses incandescent filaments for each segment.
[Dycus] has gone through three revisions of the Filawatch so far, with probably at least one more on the way. The current version is powered by a ATmega328 microcontroller with dual 16-bit LED drivers to control the filaments in the KW-104S Numitron display modules. He’s also included an accelerometer to determine when the wearer is looking at the display, and even a light sensor to control the brightness of the display depending on the ambient light level.
If there’s a downside to Numitron displays, it’s their monstrous energy consumption. Just like in the incandescent light bulbs most of us have been ditching for LED, it takes a lot of juice to get that filament glowing. [Dycus] reports the display draws as much as 350 mA while on, but by lighting it up for only five seconds at a time it can be checked around 150 times before the watch needs to be recharged.
The Synchroscope is an interesting power plant instrument which doubles up as two devices in one. If the generator frequency is not matched with the grid frequency, the rotation direction of the synchroscope pointer indicates if the frequency (generator speed) needs to be increased or decreased. When it stops rotating, the pointer angle indicates the phase difference between the generator and the grid. When [badjer1] [Chris Muncy] got his hands on an old synchroscope which had seen better days at a nuclear power plant control room, he decided to use it as the enclosure for a long-pending plan to build a Nixie Tube project. The result — an Arduino Nixie Clock and Weather Station — is a retro-modern looking instrument which indicates time, temperature, pressure and humidity and the synchroscope pointer now indicates atmospheric pressure.
Rather than replicating existing designs, he decided to build his project from scratch, learning new techniques and tricks while improving his design as he progressed. [badjer1] is a Fortran old-timer, so kudos to him for taking a plunge into the Arduino ecosystem. Other than the funky enclosure, most of the electronics are assembled from off-the-shelf modules. The synchroscope was not large enough to accommodate the electronics, so [badjer1] had to split it into two halves, and add a clear acrylic box in the middle to house it all. He stuck in a few LEDs inside the enclosure for added visual effect. Probably his biggest challenge, other than the mechanical assembly, was making sure he got the cutouts for the Nixie tubes on the display panel right. One wrong move and he would have ended up with a piece of aluminum junk and a missing face panel.
Being new to Arduino, he was careful with breaking up his code into manageable chunks, and peppering it with lots of comments, for his own, and everyone else’s, benefit. The electronics and hardware assembly are also equally well detailed, should anyone else want to attempt to replicate his build. There is still room for improvement, especially with the sensor mounting, but for now, [badjer1] seems pretty happy with the result. Check out the demo video after the break.
Vacuum tubes are awesome, and Nixies are even better. Numitrons are the new hotness, but there’s one type of tube out there that’s better than all the rest. It’s the ИГГ1-64/64M. This is a panel of tubes in a 64 by 64 grid, some with just green dots, some with green and orange, and even a red, green, blue 64 by 64 pixel matrix. They’re either phosphors or gas-filled tubes, but this is the king of all tube-based displays. Not even the RGB CRTs in a Jumbotron can match the absurdity of this tube array.
[Muth] got his hands on a few of these panels, and finally he’s displaying images on them. It’s an amazing project that involved finding the documentation, translating it, driving the tubes with 360 Volts, and figuring out a way to drive 128 inputs from just a few microcontroller pins.
First, the power supply. These panels require about 360 Volts to light up. This is significantly higher than what would usually be found in a Nixie clock or other normal tube-based display. That’s no problem, because a careful reading of the datasheet revealed a circuit that brings a normal-ish 180 Volt Nixie power supply up to the proper voltage. To drive these pixels, [Muth] settled on a rather large PIC18F microcontroller with eight tri-state buffers. The microcontroller takes data over a serial port and scans through the entire framebuffer. All in all, there are eight driver boards, 736 components, and 160 wires connecting everything together. It’s a lot of work, but now [Muth] has a 64×64 display that’s green and orange.
You can check out a ‘pixel dust’ demo of this display in action below.
Have you ever thought that Nixie tubes are cool but too hard to control with modern electronics? And that they’re just too expensive? [david.reid] apparently thought so and decided to create his own version of a Nixie tube, and it doesn’t get much cheaper than this.
While working on a 3D printed locomotive with his son, [david.reid] used clear PETG (Polyethylene Terephthalate Glycol) 3D printer filament to move light from LEDs to various parts of the locomotive. He found this was a success, but roughed up the outside of the filament to see what would happen. Lo and behold, a warm glow appeared on the surface of the tube! Like any good hacker, his next thought was of Nixie tubes, as you have seeninmanyclocks.
His basic idea is that with a little heat you can bend the filament into any shape that you like ([david.reid] uses custom molds). You then use some sandpaper to roughen up the outside wherever you’d like light to show, and add an LED at the bottom to light it up!
Like the look of Nixies but they just seem a little overdone? Or perhaps you just don’t want the hassles of a high-voltage power supply? Then maybe these faux-Nixie LED “tube” displays will find a way into your next clock build.
For his 2018 Hackaday Prize entry, [bobricius] decided that what the world needs is a Nixie that’s not a Nixie. To that end, each display is formed by seven surface-mount LEDs soldered to a seven-segment shaped PCB and slipped into a glass tube. The LEDs are in 4014 packages so they’re only 4 millimeters long, but what they lack in size they make up for in brightness. We’re not sure if it’s a trick of the camera, but the LEDs certainly seem to put off a bluish glow that’s reminiscent of vacuum-fluorescent displays — it’s like a Nixie and a VFD all rolled up in one package. The current case, which hides the clock circuitry on the lower part of the PCB, is just plastic, but this would look spiffy in a fine wooden case.
Revisiting old projects is always fun and this Nixie Clock by [pa3fwm] is just a classic. Instead of using transistors or microcontrollers, it uses neon lamps to clock and drive the Nixie Displays. The neon lamps themselves are the logic elements. Seriously, this masterpiece just oozes geekiness.
Inspired by the book “Electronic Counting Circuits” by J.B. Dance(ZIP), published in 1967, we covered the initial build a few years back. The fundamental concept of operation is similar to that of Neon Ring Counters. [Luc Small] has a write-up explaining the construction of such a device and some math associated with it. In this project, [pa3fwm] uses modern day neons that you find in indicators, so his circuit is also updated to compensate for the smaller difference in striking and maintaining voltages.
The original project was done in 2007 and has since undergone a few upgrades. [Pa3fwm] has modified the construction to make it wall mounted. Even though it’s not a precise timekeeper, the project itself is a keeper from its time. Check out the video below for a demonstration.
Love them or hate them, Nixies are here to stay. Their enduring appeal is due in no small part to the fact that they’re hardly plug-and-play; generating the high-voltage needed to drive the retro displays is part of their charm. But most Nixie power supplies seem to want 9 volts or more on the input side, which can make integrating them into the typical USB-powered microcontroller project difficult.
Fixing that problem is the idea behind [Mark Smith]’s 5-volt Nixie power supply. The overall goal is simple: 5 volts in, 170 volts out at 20 mA. But [Mark] paid special care to minimize the EMI output of the boost converter through careful design, and he managed to pack everything into a compact 14-cm² PCB. He subjected his initial design to a lot of careful experimentation to verify that he had met his design goals, and then embarked on a little tweaking mission in KiCad to trim the PCB’s footprint down by 27%. The three separate blog posts are well worth a read by anyone interested in learning about electronics design.