I’ll See Your Seven-Segment Mechanical Display And Raise You To 16 Segments

October 8, 2022 by Dan Maloney 6 Comments

Mechanical multi-segment displays have become quite a thing lately, and we couldn’t be more pleased about it. The degree of mechanical ingenuity needed to make these things not only work but look good while doing it never ceases to amaze us, especially as the number of segments increases. So we submit this over-the-top 16-segment mechanical display (Nitter) for your approval.

The original tweet by [Kango Suzuki] doesn’t have a lot of detail, especially if you can’t read Japanese, but we did a little digging and found the video shown below. It shows a lot more detail on how this mechanism works, as well as some of the challenges that cropped up while developing it. Everything is 3D printed, and flipping the state of each of the 16 segments is accomplished with a rack-and-pinion mechanism, with the pinions printed right into each two-sided cylindrical segment. The racks are connected to pushrods that hit a punch card inserted into a slot in the rear of the display. The card has holes corresponding to the pattern to be displayed; when it’s pushed home, the card activates a mechanism that slides all the racks that line up with holes and flips their segments.

This isn’t the first multi-segment mechanical masterpiece from [Kango Suzuki] that we’ve featured, of course. This wooden seven-segment display works with cams rather than punch cards, but you can clearly see the hoe the earlier mechanism developed into the current work. Both are great, and we’re looking forward to the next segment count escalation in the mechanical display wars.

Continue reading “I’ll See Your Seven-Segment Mechanical Display And Raise You To 16 Segments” →

A sliced digital file of a marker light enclosure. Background is a white and grey grid and object itself is a series of print path lines in red, orange, and green.

3D Printing Hard-To-Find Vintage Vehicle Parts

October 7, 2022 by Navarre Bartz 52 Comments

When I was growing up, my dad and I restored classic cars. Combing junkyards for the pieces we needed was a mixture of interesting and frustrating since there was always something you couldn’t find no matter how long you looked. [Emily Velasco] was frustrated by the high price of parts even when she was able to find them, so she decided to print them herself. She wrote an excellent tutorial about designing and 3D printing replica parts if you find yourself in a similar situation.

All four marker lights on [Velasco]’s 1982 Toyota pickup were on their way to plastic dust, and a full set would run her $160. Instead of shelling out a ton of cash for some tiny parts, she set out to replicate the marker lamps with her 3D printer. Using a cheap marker lamp replacement for a more popular model of pickup as a template, she was able to replace her marker lamps at a fraction of the cost of the options she found online. Continue reading “3D Printing Hard-To-Find Vintage Vehicle Parts” →

Seven Segments, But Not As We Know Them

October 6, 2022 by Donald Papp 11 Comments

We’ve seen a lot of clever re-imagining of the classic 7-segment display, and proving there is still room for something new is [Jack]’s 7-segment “DigiTag” display.

This 3D printable device has a frame into which is slotted three sliders. These sliders can be adjusted individually, mixing and matching the visibility of colored and uncolored areas, to create digits 0-9. We’ve seen some unusual 7-segment-inspired displays before, using from one motor for the whole digit to ones that need one motor per segment, but nothing quite like this approach.

While this particular design relies on the user to manually “dial in” each digit, the resulting key-like assembly (and unique shape for each digit) seems like it could have some interesting applications — a puzzle box design comes to mind.

If you have any ideas of your own on how this could be used, don’t keep them to yourself! Let us know in the comments, below.

The assembled switch PCB in the palm of its creator's hand

TTP223 Brings Simple Touch Controls To A LED Lamp

October 4, 2022 by Arya Voronova 7 Comments

You can buy small modules with capacitive touch detection ICs — most often it’s the TTP223, a single-button capacitive model with configurable output modes. These are designed to pair with a microcontroller or some simple logic-level input, but [Alain Mauer] wanted was to bring touch control to a simple LED strip. Not to be set deterred, he’s put together a simple TTP223-based switch board.

Initially, he made a prototype using one of the regular TTP223 boards as a module, but then transferred the full schematic onto a single PCB. The final board uses an NPN transistor capable of handling up to 3 amps to do the switching job, and Zener-based regulation to provide 5 V for the TTP223 itself from the 12 V input. [Alain] shares the schematic, as well as BOM together with Gerber files for a 2×3 panel in case you’re interested in adding a few of these handy boards to your parts bin.

The TTP223 is a ubiquitous and quite capable chip – we’ve seen it used for building a mouse with low actuation force buttons, a soft power switch, and even a UV-sensing talisman that’s equal parts miniature electronics and fascinating metalwork.

Continue reading “TTP223 Brings Simple Touch Controls To A LED Lamp” →

Picture showing the way the cut-down piece of chip is soldered onto the mainboard - looking, indeed, like a QFN package.

Making A Handheld NES By Turning DIP Chips Into…QFN?

October 2, 2022 by Arya Voronova 51 Comments

You can achieve a lot with a Dremel. For instance, apparently you can slim the original NES down into the hand-held form-factor. Both the CPU and the PPU (Picture Processing Unit) are 40-pin DIP chips, which makes NES minification a bit tricky. [Redherring32] wasn’t one to be stopped by this, however, and turned these DIP chips into QFN-style-mounted dies (Nitter) using little more than a Dremel cutting wheel. Why? To bring his TinyTendo handheld game console project to fruition, of course.

DIP chip contacts go out from the die using a web of metal pins called the leadframe. [Redherring32] cuts into that leadframe and leaves only the useful part of the chip on, with the leadframe pieces remaining as QFN-like contact pads. Then, the chip is mounted onto a tailored footprint on the TinyTendo PCB, connected to all the other components that are, thankfully, possible to acquire in SMD form nowadays.

This trick works consistently, and we’re no doubt going to see the TinyTendo being released as a standalone project soon. Just a year ago, we saw [Redherring32] cut into these chips, and wondered what the purpose could’ve been. Now, we know: it’s a logical continuation of his OpenTendo project, a mainboard reverse-engineering and redesign of the original NES, an effort no doubt appreciated by many a NES enthusiast out there. Usually, people don’t cut the actual chips down to a small size – instead, they cut into the mainboards in a practice called ‘trimming’, and this practice has brought us many miniature original-hardware-based game console builds over these years.

Continue reading “Making A Handheld NES By Turning DIP Chips Into…QFN?” →

This Scratch-Built X-Ray Tube Really Shines

September 24, 2022 by Dan Maloney 25 Comments

On no planet is making your own X-ray tube a good idea. But that doesn’t mean we’re not going to talk about it, because it’s pretty darn cool.

And when we say making an X-ray tube, we mean it — [atominik] worked from raw materials, like glass test tubes, tungsten welding electrodes, and bits of scrap metal, to make this dangerously delightful tube. His tool setup was minimalistic as well– where we might expect to see a glassblower’s lathe like the ones used by [Dalibor Farny] to make his custom Nixie tubes, [atominik] only had a small oxy-propane hand torch to work with. The only other specialized tools, besides the obvious vacuum pump, was a homebrew spot welder, which was used to bond metal components to the tungsten wires used for the glass-to-metal seals.

Although [atominik] made several versions, the best tube is a hot cathode design, with a thoriated tungsten cathode inside a copper focusing cup. Across from that is the anode, a copper slug target with an angled face to direct the X-rays perpendicular to the long axis of the tube. He also included a titanium electrode to create a getter to scavenge oxygen and nitrogen and improve the vacuum inside the tube. All in all, it looks pretty similar to a commercial dental X-ray tube.

The demonstration in the video below is both convincing and terrifying. He doesn’t mention the voltage he’s using across the anode, but from the cracking sound we’d guess somewhere around 25- to 30 kilovolts. The tube really gets his Geiger counter clicking.

Here’s hoping [atominik] is taking the proper precautions during these experiments, and that you do too if you decide to replicate this. You’ll also probably want to check out our look at the engineering inside commercial medical X-ray tubes.

Continue reading “This Scratch-Built X-Ray Tube Really Shines” →

Neon Lamps — Not Just For Pilot Lights

September 13, 2022 by Dan Maloney 30 Comments

It’s easy to see why LEDs largely won out over neon bulbs for pilot light applications. But for all the practical utility of LEDs, they’re found largely lacking in at least one regard over their older indicator cousins: charm. Where LEDs are cold and flat, the gentle orange glow of a neon lamp brings a lot to the aesthetics party, especially in retro builds.

But looks aren’t the only thing these tiny glow lamps have going for them, and [David Lovett] shows off some of the surprising alternate uses for neon lamps in his new video. He starts with an exploration of the venerable NE-2 bulb, which has been around forever, detailing some of its interesting electrical properties, like the difference between the voltage needed to start the neon discharge and the voltage needed to maintain it. He also shows off some cool neon lamp tricks, like using them for all sorts of multi-vibrator circuits without anything but a few resistors and capacitors added in. The real fun begins when he breaks out the MTX90 tube, which is essentially a cold cathode thyratron. The addition of a simple control grid makes for some interesting circuits, like single-tube multi-vibrators.

The upshot of all these experiments is pretty clear to anyone who’s been following [David]’s channel, which is chock full of non-conventional uses for vacuum tubes. His efforts to build a “hollow state” computer would be greatly aided by neon lamp circuits such as these — not to mention how cool they’d make everything look.

Continue reading “Neon Lamps — Not Just For Pilot Lights” →