A Quantum Magic 8-Ball

June 27, 2026 by No comments

If you ever cracked open one of those Magic 8-Ball toys, you found little more than a polyhedron floating in some dark-colored fluid. It was a quasi-random way of asking the universe to answer crucial questions like “will Mom and Dad get a divorce?” and “does Bethany like me?” even if the results were seldom accurate (sorry about your parents, kid). If you want a more reliably random 8-ball that is not even slightly more truthful, you might like this recent build from [David Noel Ng].

The concept is simple enough — leverage quantum effects that provide truly random results to seed run a random number generator that determines the outcome of a software magic 8-ball. [David] tried a few ways to build something along these lines, and eventually settled on a setup that he felt suited the task at hand.

In the final rig, a light source spits out photons, and is attenuated to the point where effectively only one photon is running through the light path at a time. Each photon passes through a beam splitter, and either passes through the mirror and hits photomultiplier A, or bounces off and hits photomultiplier B. This creates a truly random yes/no result for every photon that passes through. [David] does a great job of explaining the low-level physics at play, as well as the supporting electronics and code that turns this into a usable magic 8-ball that actually answers questions.

We’ve seen other magic 8-ball builds before, too. Few come with quite the same tactile wonder created by the original toy, but they nonetheless do the job of answering questions that are too frivolous to take to a tarot reader or local divining bog witch. If you’re whipping up your own way to deduce the wills of the fates, don’t hesitate to let us know on the tipsline.

A white man in a dark t-shirt and glasses stands next to a pegboard. On the pegboard is a cylindrical wooden bird house with a small piece of metal roof attached to the top. A set of heat lamps are suspended above and give the image a reddish-orange glow. 87˚F is in white text in the lower left corner.

Do Metal Roofs Turn A Bird House Into An Oven?

June 27, 2026 by 4 Comments

Birdhouses can be a great way to help out nesting birds in your area, but they can be a bit intensive to make. As part of a 500 birdhouse marathon, [Of Human and Nature] decided to test whether a metal roof would be safe or turn the birdhouse into an oven.

Most DIY birdhouses are made of wood to encourage cavity nesting species that would naturally find a hole in a tree to use the house. Unfortunately, an unprotected chunk of wood will deteriorate much faster than a whole tree full of holes might. A metal roof reduces the exposure to the elements, but does it make the box too hot?

[Of Human and Nature] heeded concerns from commenters and actually tested his hypothesis with a simple set of thermocouples, a heat lamp, and an assembled birdhouse. While the metal roof was held at 70˚C for four hours, the inside of the house stayed in the mid 20˚C range thanks to the separation between the roof and the actual box which allows air to flow between the two.

Maybe a metal roof could help you house your homing pigeons as well? If you want to spread the mesh with your birdhouse instead, how about a solar panel roof with a LoRa node?

Continue reading “Do Metal Roofs Turn A Bird House Into An Oven?” →

Watch YouTube On A Game Boy Color With A Special Cartridge

June 26, 2026 by 4 Comments

There’s no questioning [Throaty Mumbo]’s uncanny skill at answering questions that nobody ever asked, such as whether it’s possible to watch YouTube videos on a Nintendo Game Boy Color handheld gaming system.

Of course the answer here is a resounding ‘sorta’, loosely defined by what you mean with ‘watch’ and ‘video’ exactly. For the impatient there’s the GitHub project page with the project summary, along with a detailed video containing hijinks and a playback demo on real Game Boy Color hardware with the cobbled-together GBCTube cartridge.

The nice thing about these cartridge-based gaming systems is that you get direct access to the system’s hardware via the cartridge bus, with for systems like the GBC a basic cartridge PCB readily available if you’re feeling that prototyping itch.

Such a cartridge breakout board for the GBC was thus used as the core of this project, with an ESP32-C6 acting solely as Wi-Fi bridge for the RP2350B MCU which handles basic player firmware and bridging duty between the GBC and the streamed video data from the host PC. It’s the latter does the heavy lifting of wrangling the YouTube experience into something that sort of works on the GBC’s amazing, very vibrant, backlight-free 160×144 resolution color LCD.

With the cartridge inserted you can search for a video title on the GBC, select a video which is then downloaded with yt-dlp on the host PC and prepared for streaming. Audio is handled by the RP2350B to free up CPU cycles on the GBC, for which a separate speaker is slapped into the cartridge for high-fidelity mostly-synced audio.

Perhaps the most fascinating question that one is left with is whether a more powerful Espressif MCU like e.g. the ESP32-S31 could combine all these tasks into a single package. Not because there’s a particular reason to do so, but more out of sheer morbid curiosity, perhaps.

Continue reading “Watch YouTube On A Game Boy Color With A Special Cartridge” →

NVIDIA’s New AI Servers Run On Hotub Coolant And Don’t Need Evaporators

June 26, 2026 by 13 Comments

When people start ranting about AI, you can be sure a few things are going to come up during the two-minutes hate: job loss, higher power bills, the neverending tide of low-effort slop, and wasting precious freshwater. Well, NVIDIA wants to take away that last one, beacause the all-water cooled Ruben architecture won’t need any evaporative cooling— coolant can stay in a closed loop, and never needs to be cooled below 45 C, or 113 F.

This sort of coolant loop should be familiar to anyone who has ever built a water-cooled PC or PlayStation: there’s a glycol-water mix, water blocks, and a radiator to reject heat to the environment. NVIDIA doesn’t mention if their new servers come with RGB lighting, but we’d like to imagine it’s an option. The big difference — aside from the rainbow LEDs– between a Ruben server and your old gaming rig is that in these racks, everything is on a waterblock. If there’s a chip on the motherboard generating heat, it’s getting rid of it into the same cooling water. Cooling water, that we have to emphasize, needs only be cooler than the chips themselves: in this case, they’re talking 45 C on the cold side, and 55 C headed out of the racks. (That’s 113 F to 131 F for all the bald eagles reading this.)

Given the required temperature drop is so modest, there’s no need for the evaporative chillers that have given AI data centers such a bad name in water conservation circles. Just like in a water-cooled PC, ambient-temperature air running over dry heat exchangers– also known as big honkin’ radiators–is able to handle the cooling, so no water is lost. Since everything is on waterblocks, there’s no need for cooling air, either, and the server farms need only be air conditioned to the degree required to make them comfortable to work in.

If you think NVIDIA is making this change because they suddenly care about water conservation, think again. The press release makes their motivations very clear: cooling costs money, and running this hot saves a lot of it. We’re talking four mil US a year for a 50 MW hyperscaler. One might suspect that this sort of thermal regime could limit the lifetime of the hard-working NPUs, but since they’ll be obsolete in a few years anyway, that’s not likely a big concern, especially not for NVIDIA.

We’ve actually seen hotter fluids used to cool computers before– coffee, for one. Water cooling also isn’t new in the data center world; we took a look at it a few years back. Things are clearly heating up now, though.

Fixing An Elgato Cam Link’s USB Current Draw Issue

June 26, 2026 by 9 Comments

Recently [Bits und Bolts] found himself in a bit of a pickle, when on boot his PC would complain about a connected USB device drawing too much power, before shutting down again. After unplugging various USB devices, the problem was narrowed down to an Elgato Cam Link 4K video capture device.

Some prodding and poking around with a thermal camera on the disassembled device while powered showed that an onboard IC had sprung a power leak. Sadly, even asking nicely, Elgato support wasn’t going to provide board-level repair help, so this was left as an exercise to the owner.

Although the markings on the chip didn’t offer much help, it turns out that this is a more common issue, with a convenient repair guide by [Uldis Melderis] identifying the part as the TI TLV62585 buck regulator.

After purchasing a couple of spares, the defective IC could then be replaced. Following this a quick test showing decidedly less angry electrons. From there it was a matter of reassembling the device in its plastic case and seeing whether the PC was happier with the now hopefully fixed device, which fortunately turned out to be the case.

Any such analysis and repair obviously raises a number of questions, such as why these buck regulators are dying, and why you’re supposed to just toss out a $100 device instead of doing a repair involving a $0.20 part and a few minutes with a hot air gun.

A Custom Zigbee Touch Keypad

June 26, 2026 by 1 Comment

[Dominic Buchstaller] wanted a neat, tidy entryway keypad that actually looked good. Prime goals were something slim, wireless, and with no visible screws. Dependency on the cloud was also a no-go. With few ready-to-go options available on the market, he set about whipping up his own.

The heart of the build is an ESP32-C6 microcontroller devboard. This device has the benefit of including Zigbee communication functionality baked right into the chip. It’s hooked up to an MPR121 capacitive touch controller, which allows different segments of the touchpad PCB to act as capacitive buttons for numerical entry. The number labels are directly printed on the PCB solder mask, so there’s no overlay or other label required on top. Power is courtesy of a 1300 mAh lithium-polymer cell which gives a useful lifespan of six months between recharges. A simple 3D-printed case holds everything together and completes the clean and simple look. [Dominic] notes that it’s possible to also use the device via Matter or Thread without a lot of changes, as the ESP32-C6 can easily handle those protocols, too.

If you’re looking for a cheap, handsome keypad for your Home Assistant setup or similar, you might find this useful. We’ve explored DIY keypad entry systems before, too. If you’ve come up with some other creative way to get into your house, car, or bank vault, be sure to notify us via the tipsline.

Reflective LCD Slabtop Terminal Runs Homebrewed Solar OS

June 26, 2026 by 12 Comments

Have you ever spotted something in a catalog or on a website and just known you had to build a project around that one part? That’s how [nilseuropa] felt about the Waveshare ESP32-S3-RLCD-4.2, which — as you might guess from the name — pairs an ESP32-S3 with a reflective LCD. With a screen reminiscent of a palmtop of yore, [nilseuropa] wanted a personal device, and needed something to run on it. That’s where Solar OS comes in.

Physically he’s paired the Waveshare board with a mini keyboard and put them together in a handsome 3D printed case with a battery. The slabtop form-factor was more for ease-of-creation than any preference; in the project’s reddit thread [nils] is reaching out for help making something cooler, possibly of the palmtop form-factor. He also describes some of the thinking behind his operating system.

You had us at “terminal”.

He’s not starting entirely from scratch: it’s based on FreeRTOS and the ESP-IDE toolset. Right now all applications are built with the OS into a single binary, while the SD card on the Waveshare board handles persistent storage. The interface is pure text, with all applications launched via shell commands. That doesn’t mean you have to go back to your PC to add anything, however.

The system is user-programmable, with Python and Lua scripting as “first class citizens”, having access to the hardware through the Solar OS APIs. As for the applications built into the firmware, it looks like along with the serial terminal, you get quite a lot: an orthodox file manager à la Norton Commander, networking tools that include a web browser and chat client, MP3 player, image viewer, text editor, games, and more.

While they are obviously pretty niche projects, we do appreciate that there’s a growing collection of homebrew operating systems that you can run on your bespoke computing device.