Magic-less 8 Ball Finds New Life With Pi Pico Inside

There’s an old saying that goes: when life gives you lemons, make lemonade. [lds133] must have heard that saying, because when life took the magic liquid out of his Magic 8 Ball, [lds133] made not eight-ball-aide, but an electronic replacement with a Raspberry Pi Pico and a round TFT display.

In case the Magic 8 Ball is unknown in some corners of the globe, it is a toy that consists of a twenty-sided die with a set of oracular messages engraved on it, enclosed in a magical blue liquid — and by magical, we mean isopropyl alcohol and dye. The traditional use is to ask a question, shake the eight-ball, and then ignore its advice and do whatever you wanted to do anyway.

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Making A Nichrome Wirewound Power Resistor

Although not really a cost-effective or a required skill unless you have some very specific needs not met by off-the-shelf power resistor options, making your own own wirewound power resistor is definitely educational, as well as a fascinating look at a common part that few people spare a thought on. Cue [TheElectronBench]’s video tutorial on how to make one of these components from scratch.

The resistance value is determined by the length of nichrome wire, which is an alloy of nickel and chromium (NiCr) with a resistivity of around 1.12 µΩ/m. It’s also extremely durable when heated, as it forms a protective outer layer of chromium oxide. This makes it suitable for very high power levels, but also requires the rest of the power resistor assembly to be able to take a similar punishment.

For the inner tube of this DIY power resistor a tube of alumina ceramic was used, around which the nichrome wire is wound. This resistor targets 15 Ohm at a maximum load of 50 Watt, this means a current of about 1.83 A is expected at 27.4 V. The used nichrome wire has a measured resistance of 10.4 Ohm, ergo 1.44 meter has to be cut and wound.

This entire assembly is then embedded in refractory cement (fireproof cement), as this will keep the wire in place, while also able to take the intense temperature cycling during operation. As a bonus this will prevent toasting the surrounding environment too much, never mind lighting things on fire as the nichrome wire heats up.

As explained in the video, this is hardly the only way to create such a power resistor, with multiple types of alternative alloys available, different cores to wind around and various options to embed the assembly. The demonstrated method is however one that should give solid results and be well within the capabilities and budget of a hobbyist.

An important point with nichrome is that you cannot really solder to it, so you’ll need something along the lines of a mechanical (crimping) connection. There are also different winding methods that can affect the inductance of the resistor, since this type of resistor is by its design also a coil. This is however not covered in the video as for most applications it’s not an issue.

Overall, this video tutorial would seem to be a solid introduction to nichrome power resistors, including coverage of many issues you may encounter along the way. Feel free to sound off in the comment section with your own experiences with power resistors, especially if you made them as well.

SEGA Music To MODfile, (Semi)Automatically

One thing SEGA’s MegaDrive/Genisis and the Commodore Amiga had in common was–aside from the Motorola 68000 processor– being known for excellent music in games. As [reassembler] continues his quest to de-assemble Sonic: The Hedgehog and re-assemble the code to run on Amiga, getting the music right is a key challenge. Rather than pull MIDI info or recreate the sound by ear, [reassembler] has written a program called Sonic2MOD to automatically take the assembly file music from the MegaDrive catridge and turn it into an Amiga-style MODfile. He’s also made a video about it that you’ll find embedded below.

Of course how music gets made differs widly on the two systems. Amiga, famously has Paula, a custom ASIC designed for sampling, allowing you to play four eight-bit voices. The Sega, of course, has that glorious FM-synthesis chip from Yamaha synthesizing five channels of CD-quality sound and one channel of sample. It’s not as well known, but the Sega also has a bonus TI-compatible programmable sound chip (PSG) that can handle 3 square-wave tone channels and one noise channel. That’s ten total channels to the Amiga’s four, and CD-quality to 8-bit voices. Knowing all that, we were very curious how close to SEGA’s original music [reassembler] could get on the Amiga.

Before he could show us, [reassembler] needed to decode the SMPS files used on Sonic: The Hedgehog and many other MegaDrive games. Presumably he could have gotten a MIDI file online somewhere– there are oodles– but the goal was to reverse engineer Sonic from its cartridge for the Amiga, not download a lot of resources from the web. SMPS is a sort of programing language for sound, telling the Yamaha and PSG chips what to do.

In some ways, it’s not unlike the Amiga’s MOD format, which programmatically specifies how to play the sampled voices also stored in the file. Translating from one to another is a matter of reading the SMPS files, extracting the timing, volume, vibrato, et cetera, and translate that into a form the MOD file can use. Then [reassembler] needed to generate samples, which was an added hiccup because the Amiga can only handle 3 octaves vs the seven of the SEGA’s FM synthesizer. He’s able to solve this simply by generating multiple samples to span the Yamaha chip’s range, though, again, at only 8-bit fidelity. It doesn’t sound half bad.

What about the four-channel limit? That’s where a bit of artistry comes in; the automated tool produces MOD files with more voices, which MOD trackers can handle at increased computational load. Computational load you don’t need when trying to play a game. Scaling down the soundtrack to the Amiga’s limits is something [reassembler] already has practice with from his famous OutRun port, though, so we’re sure he’ll get it done.

All of this effort just to match the Mega Drive makes us appreciate what a capable little computer the Sega console was; why, you can even check your stocks with it! We’ve already featured [reassembler]’s Sonic port once before, but this music tool was interesting enough we couldn’t help ourselves coming back to it. The ability to play MOD files were pretty impressive when the Amiga came out, but nowadays all you need is a ten-cent microcontroller.

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Using FireWire On A Raspberry Pi Before Linux Drops Support

Once the premium option for data transfers and remote control for high-end audiovisual and other devices, FireWire (IEEE 1394) has been dying a slow death ever since Apple and Sony switched over to USB. Recently Apple correspondingly dropped support for it in MacOS 26, and Linux will follow in 2029. The bright side of this when you’re someone like [Jeff Geerling] is that this means three more years of Linux support for one’s FireWire gear, including on the Raspberry Pi with prosumer gear from 1999.

If you’re not concerned about running the latest and greatest – and supported – software, then using an old or modern Mac or PC is of course an option, but with Linux support still available [Jeff] really wanted to get it working on Linux. Particularly on a Raspberry Pi in order to stay on brand.

Adding a FireWire port to a Raspberry Pi SBC is easy enough with an RPi 5 board as you can put a Mini PCIe HAT on it into which you slot a mini PCIe to Firewire adapter. At this point lspci shows the new device, but to use it you need to recompile the Linux kernel with Firewire support. On the Raspberry Pi you then also need to enable it in the device tree overlay, as shown in the article.

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Water Cooling The MacBook Neo Laptop To Double Gaming Performance

Recently [ETA Prime] felt a bit underwhelmed by the raw performance of his MacBook Neo when it came to running for extended periods under full load, such as when gaming. Thus the obvious solution is to mildly over-engineer a cooling solution that takes care of issues like thermal throttling.

The Apple MacBook Neo with its repurposed iPhone 16 SoC seems to have leaned hard into answering the question whether a smartphone can be a good general purpose personal computer. Ignoring the lack of I/O, it’s overall not a bad SoC for a laptop, but like when you try to push the CPU and GPU on a smartphone, they do get pretty toasty. Due to the minimalistic cooling solution in the MacBook Neo it’ll easily hit the 105°C thermal throttle limit.

Technically the ‘heatsink’ for this laptop is the aluminium case, as the SoC is coupled via a thermal pad to the case. This doesn’t leave a lot of space and the case will heat soak pretty fast, while also making retrofitting a cooling solution a challenge.

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Laser Welding Helps YouTuber Get Ahead With Aluminum Sheet

Laser Welding is apparently the new hotness, in part because these sci-fi rayguns masquerading as tools are really cool. They cut! They weld! They Julienne Fry! Well, maybe not that last one. In any case, perhaps feeling the need to cancel out that coolness as quickly as he possibly could, YouTuber [Wesley Treat] decided to make a giant version of his own head.

[Wesely] had previously been 3D scanned as part of the maker scans project, which you can find over on Printables. Those of you who really hate YouTubers, take note: finally you have something  to take your frustrations out on. [Wesely] takes that model into Blender to decimate and decapitate– fans of the band Tyr may wonder if the model questioned his sword–before feeding that head through an online papercraft tool called PaperMaker to generate cut files for his CNC. There are also a lot of welding montages interspersed there as he practices with the new tool. [Wesely] did first try out his new raygun on steel in a previous video, but even knowing that, he makes the learning curve on these lasers look quite scalable.

While we’re not likely to follow in [Wesely]’s footsteps and create our own low-poly Zardoz– Zardozes? Zardii?– using a papercraft toolchain and CNC equipment with sheet aluminum is absolutely a great idea worth stealing. It’s very similar to what another hacker did with PCBs— though that project was perhaps more reasonable in scale and ego.

We are no strangers to papercrafts that use actual paper here, either, having featured everything from model retrocomputers to fully-mobile strandbeasts. 

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Use A Gap-Cap To Embed Hardware In Your Next 3D Print

Embedding fasteners or other hardware into 3D prints is a useful technique, but it can bring challenges when applied to large or non-flat objects. The solution? Use a gap-cap.

The gap-cap technique is essentially a 3D printed lid. One pauses a print, inserts hardware, then covers it with a lid before resuming the print. The lid — or gap-cap — does three things. It seals in the part, it fills in empty space left above the component, and it provides a nice flat surface for subsequent layers which makes the whole process much cleaner and more reliable.

This whole technique is a bit reminiscent of the idea of manual supports, except that the inserted piece is intended to be sealed into the print along with the embedded hardware under it.

If you have never inserted anything larger than a nut or small magnet into a 3D print, you may wonder why one needs to bother with a gap-cap at all. The short version is that what works for printing over small bits doesn’t reliably carry over to big, odd-shaped bits.

For one thing, filament generally doesn’t like to stick to embedded hardware. As the size of the inserted object increases, especially if it isn’t flat, it increasingly complicates the printer’s ability to seal it in cleanly. Because most nuts are small, even if the printer gets a little messy it probably doesn’t matter much. But what works for small nuts won’t work for something like an LED strip mounted on its side, as shown here.

Cross-section of a print with an embedded LED strip. The print pauses (A), LED strip is inserted and capped with a gap-cap (B, C), then printing resumes and completes (D).

In cases like these a gap-cap is ideal. By pre-printing a form-fitting cap that covers the inserted hardware, one provides a smooth and flat surface that both seals the component in snugly while providing an ideal surface upon which to resume printing.

If needed, a bit of glue can help ensure a gap-cap doesn’t shift and cause trouble when printing resumes, but we can’t help but recall the pause-and-attach technique of embedding printed elements with the help of a LEGO-like connection. Perhaps a gap-cap designed in such a way would avoid needing any kind of adhesive at all.