Audio Spectrum Analyzer On An ESP32 Display Board

September 23, 2026 by No comments

A slick spectrum analyzer used to be the kind of thing that would have been tricky to include in a DIY project, but as [Mirko “mircemk” Pavleski] demonstrates, a modern microcontroller like the ESP32 can handle the task with nothing more than a display panel and a few passives.

This particular example is built around the CrowPanel 3.5, which combines the powerful microcontroller with a 480×320 touch screen LCD. But there’s nothing inherently special about the CrowPanel, and you could get similar results with whatever display you might have kicking around the parts bin — albeit potentially with some code changes to account for the different hardware.

Beyond the microcontroller and the display, all you need to recreate what [mircemk] has done here is a handful of passives to tame the incoming analog audio signal so it can be piped into one of the analog-to-digital converter (ADC) pins on the MCU.

This project is fairly simple, but if you’re looking for something a little more advanced from [mircemk], don’t worry. The more daring home players can try their hand at recreating this high-voltage X-ray machine made from an old TV vacuum tube.

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A Tiny Toy Synth For Smaller Computers

September 23, 2026 by 2 Comments

Even for the non-musical among us there is a lot of fun to be had with a simple synthesiser and sequencer, as the different controls can be manipulated to show their effect on the sound. Beeper, from [Valentyn Danylchuk] is just such a synth, and with only built-in loops, it has a focus on the instrument rather than the arrangement. What you get are a simple set of controls, from which you can modify the sound to your liking. We’ve been playing with it here, and it’s surprisingly addictive.

The target for Beeper is ESP32 microcontrollers, with builds for the S3 and P4, but there’s also a web version and one for the Mac. It’s operated using the arrow keys on your keyboard, and  the web one at least isn’t the most responsive piece of software. Below the break you can see (and hear) it on a Tanmatsu ESP32-P4 based handheld computer.

It’s certain that there are more accomplished synthesisers and sequencers to be found, but there’s still a place for one that’s simply a musical toy like this. Sometimes playing with something is more important than achieving something with it.

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Modern USB Controllers On Win98 (and Up)

September 23, 2026 by 15 Comments

[Yeo Kheng Meng] has a problem: he likes Windows 98, but he also likes his 2020 ThinkPad, which only has an xHCI USB controller– you know, the kind needed for USB 3.0, something that post-dates Windows 98 by a full decade. Drivers? Finding none existed, he decided to do it himself, or at least guide the process of using  LLMs to produce drivers for Windows 98 and up.

Some of you just stopped reading, but can you blame him for making a demonic pact for this project? Driver development isn’t really a one-man show, especially as a part-time hobby project you’re not sure anyone else will ever use. If you do want to use it, you can find the code on GitHub.

It does work, though, he admits it might be buggy. Unlike purely vibe-coded projects, [Meng] intends to address bugs put forth in the repo, at least. If you want to know how he did it, check out the link to [Meng]’s blog– which is human-authored, we can tell– and the videos embedded therein. He demonstrates it working on a 2020 ThinkPad, which should be usable even with Windows 11, and another model from 2016– neither of which have any old-style USB ports. Older laptops might, while any desktop can just use a PCI card with a USB2.0 controller– or you can do like [Meng] did prior to this project, and use the PCI card via adapters. 

[Yeo Kheng Meng] evidently gets as much of a kick out of joining old and new as we do, like running DOS a modern ThinkPad X13, and running Slack on Windows 3.11 For Workgroups on a slightly-less-modern but still 21st Century Thinkpad T400.

Smelting Bog Ore As It Should Be Done

September 23, 2026 by 6 Comments

Sometimes along comes a hack with a personal angle, and in a video showing Irish bog ore smelting, we find an appropriate follow up to a Hackaday expedition back in 2019. [Alec Steele] joined Irish Bloomery Iron, for a weekend with a medieval blast furnace.

Our brush with bog ore came in a trip to Hack42 in Arnhem, the Netherlands, where a team of Dutch hackers built a furnace from firebricks in an attempt to do the same thing. The Dutch attempt ended with a lot of mixed slag and very little iron, and looking at how the Irish furnace was constructed we see some clues to their success. Their air injection using a perforated sheet of clay and the air blast injected to form a venturi is particularly interesting,as is the shape of the furnace.

The iron bloom is lifted out through the top of the furnace rather than being tapped as molten iron, and we’re treated to it being worked into a usable bar of iron. Having spent a day with our Dutch friends doing the same work only to have scraps of iron, we’re mightily impressed with the results from the Irish smelters. You can visit their website at www.irishbloomeryiron.com.

A Mini’s Infotainment System And The Joys Of Aftermarket Car Parts

September 23, 2026 by 5 Comments

Although [Arkandas] disclaims any interest in being a ‘car guy’, this is somewhat ironic in light of the sheer amount of modding he has performed on a range of cars over the years, a recent misadventure involving a BMW Mini F56’s infotainment system replacement and some light ECU reprogramming included. What happened exactly is covered in a detailed breakdown in a blog post.

The old iDrive infotainment system in the Mini. (Credit: Arkandas)
The old iDrive infotainment system in the Mini. (Credit: Arkandas)

One of the aspects that [Arkandas] disliked about this car was its iDrive infotainment system, itself a stripped-down version of the full-fat infotainment system in ‘real’ BMW cars, with a small screen and awkward UX. The idea was to replace this with a more full-featured modern system.

Since the infotainment system does hook into the car’s CAN buses and other systems it has to be compatible, of course. This took some research before ultimately a fancy €700 aftermarket replacement was ordered from a Chinese seller.

Long story short, the device was mostly compatible aside from a connector wired wrongly and creating a short. This was fixed, but then the loosely fitted display toppled off during a test drive and broke, so a replacement screen was ordered. This screen arrived without requisite factory programming, so [Arkandas] embarked on a long reverse-engineering session.

Before he was able to extract firmware from the broken display and flash it onto the new display he was offered a brand-new replacement for the whole device, which he accepted in return for sending the old unit back. Although this still left him with a range of questions, at least the new infotainment looks pretty spiffy.

The worst part about the whole experience was just how much waiting and agonizing over poor after-sale support was involved, along with all the things that can go wrong and turn a fun afternoon of fitting shiny new parts into a months-long ordeal. Since modern cars are basically just a stack of computers on wheels, this ensures that even ‘not car guys’ will be doing a lot more of such fun car modding.

Forget Trees, Add Fins To Your 3D Prints Instead

September 23, 2026 by 10 Comments

Perhaps one of the most contentious issues in 3D printing is that of supports, both because they’re an uncomfortable reminder of how gravity affects our prints and because the very idea of there being ‘one right way’ is bound to get you into some spirited discussions. That said, [Matthew Trahan] figured that neither regular grid supports nor organic tree supports are the answer here, and that the better answer is found in fins.

The problem with existing support approaches especially with FDM prints is that they can be fairly wasteful in terms of material, and they can leave serious marks on the printed object’s surface that require post-processing. These fins on the other hand are designed to require as little material as possible and snap off as cleanly as possible. The tool, developed with the assistance of Claude, can either run locally or be accessed via printfins.com.

Currently the idea is that these fins are baked directly into the STL model so that it’s a one-time thing, but it may eventually become available as a slicer plugin. The basic concept was pitched by [Slant3D], who gets credited in the video below, although in their approach they used CAD software to add the fin supports manually.

The fins are there to provide the support base, while small tines can be added to reinforce the connection to the model. These do make it less easy to snap off with minimal scarring, of course. Conceivably these fins could be made even more light-weight by adding gaps, but that probably would add to the print time.

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2026 Hackaday Supercon: Announcing Our First Round Of Speakers

September 23, 2026 by No comments

Supercon is the Ultimate Hardware Conference™ and you need to be there November 6-8 in Pasadena, California! Below is just the tip of the speakers’ iceberg, but if that’s not enough to convince you to attend, well, stay tuned and we’ll reveal more speakers early next week.

Speakers, workshops, food, drink, music, badge hacking, and general merriment? That’s what we do every year at our annual gathering. This year is even bigger, as we’re moving a few blocks south to the Art Center campus, so be sure to come join us. Get your tickets now.

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