Not Your Average Nixie Tube Clock

November 9, 2021 by 10 Comments

When it comes to Nixie clocks, we all pretty much know what to expect: a bunch of Nixies with some RGB LEDs underneath, a wooden case of some sort, and maybe some brass gears or fittings for that authentic steampunk look. It’s not that we don’t appreciate these builds, but the convergent designs can be a little much sometimes. Thankfully, this 60-tube Nixie clock bears that mold, and in a big way.

The key to [limpkin]’s design is the IN-9 Nixie, which is the long, skinny tube that used to show up as linear indicators; think bar graph displays on bench multimeters or the VU meters on mixing boards. [limpkin] realized that 60 on the tubes could be arranged radially to represent hours or minutes, and potentially so much more. The length of the segment that lights up in the IN-9 is controlled by the current through the tube, so [limpkin] designed a simple driver for each segment that takes a PWM signal as its input. The job of a 60-channel, 14-bit PWM controller fell to an FPGA. An ESP8266 — all the rage five years ago when he started the project — took care of timekeeping and control, as well as driving a more traditional clock display of four 7-segment LEDs in the center of the clock face.

The custom PCB lives in a CNC-machined MDF wood face; the IN-9s shine through slots in the face, while the seven-segment display shows through a thinned area. It looks pretty cool, and there are a lot of display options, like the audio spectrograph shown in the video below. We’re glad [limpkin] decided to share this one after all this time.

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Teardown: Analog Radionic Analyzer

November 9, 2021 by 67 Comments

Have you ever looked up a recipe online, and before you got to the ingredients, you had to scroll through somebody’s meandering life story? You just want to know how many cans of tomato paste to buy, but instead you’re reading about cozy winter nights at grandma’s house? Well, that’s where you are right now, friend. Except instead of wanting to know what goes in a lasagna, you just want to see the inside of some weirdo alternative medicine gadget. I get it, and wouldn’t blame you for skipping ahead, but I would be remiss to start this month’s teardown without a bit of explanation as to how it came into my possession.

So if you’ll indulge me for a moment, I’ll tell you a story about an exceptionally generous patron, and the incredible wealth of sham medical hokum that they have bestowed upon the Hackaday community…

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Flip-Dot Oscilloscope Is Flippin’ Awesome

November 9, 2021 by 6 Comments

Oscilloscope displays have come a long way since the round phosphor-coated CRTs that adorned laboratories of old. Most modern scopes ship with huge, high-definition touch screens that, while beautiful, certainly lack a bit of the character that classic scopes brought to the bench. It’s a good thing that hackers like [bitluni] are around to help remedy this. His contribution takes the form of what may be both the world’s coolest and least useful oscilloscope: one with a flip-dot display.

Yup — a flip-dot display, in all it’s clickedy-clacky, 25×16 pixel glory. The scope can’t trigger, its maximum amplitude is only a couple of volts, and its refresh rate is, well, visible, but it looks incredible. The scope is controlled by an ESP32, which reads the analog signal being measured. It then displays the signal via an array of driver ICs, which allow it to update the dots one column at a time by powering the tiny electromagnets that flip over each colored panel.

Even better, [bitluni] live-streamed the entire build. That’s right, if you want to watch approximately 30 hours of video covering everything from first actuating a pixel on the display to designing and assembling a PCB to drive it, then you’re in luck. For the rest of us, he was kind enough to make a much shorter summary video you can watch below. Of course, this scope doesn’t run Doom like some others, but its probably only a matter of time.

Thank to [Zane Atkins] for the tip!

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Development Of Magnetic Locking Idea Shows Great Progress

November 9, 2021 by 18 Comments

No matter how its done, with whatever level of fakery, magnetic levitation just looks cool.  We don’t know about you, but merely walking past the tackiest gadget shop, the displays of levitating and rotating objects always catches our eye. Superconductors aside, these devices are pretty much all operating in the same way; an object with a permanent rare-earth magnet is held in a stable position between a pair of electromagnets one above and one below, with some control electronics to adjust the field strength and close the loop.

But, there may be another way, albeit a rather special case, where a magnet can not only be levitated, but locked in place using a rotating magnetic field. The video shows a demonstration of how the mass of a magnet can be used to phase lock it against a rotating field. In essence, the magnet will want to rotate to align with the rotating magnetic field, but its mass will mean there is a time delay for the force to act and rotation to occur, which will lag the rotating magnetic field, and if it is phased just so, the rotation will be cancelled and the magnet will be locked in a stable position. Essentially the inertia of the magnet can be leveraged to counteract magnet’s tendency to rapidly rotate to find a stable position in the field.

Whilst the idea is not new, Turkish experimenter [Hamdi Ucar] has been working on this subject for some time (checkout his YouTube channel for a LOT of content on it), even going as far as to publish a very detailed academic paper on the subject. With our explanation here we’re trying to simplify the subject for the sake of brevity, but since the paper has a lot of gory details for the physicists among you, if you can handle the maths, you can come to your own conclusions.

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the conversion from hynix SRAM to FRAM on a Pokemon Yellow PCB

Pokemon Time Capsule

November 8, 2021 by 17 Comments

The precious Pokemon we spent hours capturing in the early nineties remain trapped, not just by pokeballs, but within a cartridge ravaged by time. Generally, Pokemon games before the GameBoy Advance era had SRAM and a small coin cell to save state as NVRAM (Non-volatile random access memory) was more expensive. These coin cells last 10-15 years, and many of the Pokemon games came out 20 years ago. [9943246367] decided to ditch the battery and swap the SRAM for a proper NVRAM on a Pokemon Yellow cartridge, 23 years later.

The magic that makes it work is a FRAM (ferroelectric random access memory) made by Cypress that is pin-compatible with the 256K SRAM (made by SK Hynix) on the original game cartridge PCB. While FRAM data will only last 10 years, it is a write-after-read process so as long as you load your save file every 10 years, you can keep your Pokemon going for decades. For stability, [9943246367] added a 10k pull-up on the inverted CE (chip enable) pin to make sure the FRAM is disabled when not in use. A quick test shows it works beautifully. Overall, a clever and easy to have to preserve your Pokemon properly.

Since you’re replacing the chip, you will lose the data if you haven’t already. Perhaps you can use [Selim’s] Pokemon Transporter to transport your pokemon safely from the SRAM to the FRAM.

South Korean KSLV-2 Nuri Rocket Almost Orbits

November 8, 2021 by 4 Comments

There was a bit of excitement recently at the Naro Space Center on Outer Naro Island, just off the southern coast of the Korea Peninsula. The domestically developed South Korean Nuri rocket departed on its inaugural flight from launch pad LB-2 at 5pm in the afternoon on Thursday, 21 Oct. The previous launch in the KSLV-2 program from this facility was in 2018, when a single-stage Test Launch Vehicle was successfully flown and proved out the basic vehicle and its KRE-075 engines.

This final version of the three-stage Nuri rocket, formally known as Korean Space Launch Vehicle-II (KSLV-2), is 47.2 m long and 3.5 m in diameter. The first stage is powered by a cluster of four KRE-075 sea-level engines having 3 MN of thrust. The second stage is a single KRE-075 vacuum engine with 788 kN thrust, and the final stage is a KRE-007 vacuum engine with 69 kN thrust (all these engines are fueled by Jet-A / LOX). In this maiden flight, the first two stages performed as expected, but something went wrong when the third stage shut off prematurely and failed to gain enough velocity to put the 1400 kg dummy satellite into orbit.

A committee formed to investigate the flight failure convened this week, and issued a statement after a preliminary review of the collected telemetry data. So far, all indications point to a drop in oxidizer tank pressure in the third stage. This could be the result of a leak in the tank itself or the associated plumbing. They will also investigate whether a sensor or other failure in the tank pressurization control system could be at fault. A second launch is currently scheduled for May of next year. Check out [Scott Manley]’s video below the break, where he discusses the launch itself and some history of South Korea’s space program.

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Visualizing Audio With An LCD VU Meter

November 8, 2021 by 6 Comments

We all love seeing data represented in pretty ways — whether it’s necessary or not. Take VU meters for example. They’re a super useful tool for audio editors to balance signals, but they also look really cool, even if you’re only listening to music. Who didn’t use a Winamp skin with a built-in VU meter back in the day? Even after the demise of everyone’s favorite media player, we still see these great graphs popping up all over the place.

Most recently, we’ve seen VU meters circle back around to have a bit of a retro vibe in this awesome Arduino-controlled LCD VU meter built by [mircemk]. Based on the KTAudio VU Meter project, it features an ultra-wide LCD, audio input, and volume knob, all tidily wrapped up in a case whose color scheme that can only conjure images of the famed Altair 8800, or an old Tektronix oscilloscope. The LCD itself is fairly responsive — but you can judge for yourself in the video below. The signature fading that so commonly accompanies screen refreshes on LCDs such as this one really adds to the retro effect.

You may just need one of these displays on your desk — after all, while you may not need to know how loud each audio channel is, don’t you at least want the information available? Just in case. Bar graph display a bit too modern-looking for you? Well then you should check out [mircemk]’s OLED version that displays dual analog meters.

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