At Last, A Gameboy Advance With Decent Audio

August 24, 2026 by Jenny List 2 Comments

Many pieces of consumer electronics are build down to a price, and the corners cut show up in their performance. The Gameboy Advance from Nintendo is no exception: its audio is a PWM stream that sounds awful through the included amplifier. [Cajun Panda] has a fix though, in the form of a replacement audio chain.

It takes the form of a PCB that hooks into the pads of the removed GBA audio chip, and provides a much cleaner audio path with filtering and EQ and a class D audio amplifier. In addition there’s an audio codec and an ESP32 for Bluetooth connectivity, enabled by a long press of a GBA button and configured via a web interface on the ESP. Best of all there is no case modification, this is designed to remain as stock as possible.

Everything can be found in a GitHub repository should you wish to make your own, so if you want to bring your GBA audio up to scratch you know where to go. If you want to make it even better don’t forget, you can always upgrade the screen.

A man's hand is shown holding two small circuit boards, joined together by a central bridge. Each circuit board is connected to four wires and a coaxial antenna cable.

Open-Source ExpressLRS Receiver Reaches For Range

August 22, 2026 by Aaron Beckendorf 33 Comments

Drone control links are, from a radio signals perspective, nothing short of amazing: using a transmitter capable of transmitting, at most, one watt, a protocol such as ExpressLRS (ELRS) can control a drone over 100 kilometers away. [Stan], who has been building a drone electronics stack from scratch, recently designed four ELRS receivers and went over the principles behind their incredible range.

Up to a certain point, the simplest way to increase a radio’s range is to lower the frequency; lower radio frequencies penetrate better through most materials and don’t attenuate as quickly with distance. However, although ELRS can use 900 MHz bands, [Stan]’s receivers primarily use 2.4 GHz. The major improvement is in modulation: unlike other control protocols, which mostly use frequency modulation, or Wi-Fi, which uses phase and amplitude modulation, ELRS uses Chirp Spread Spectrum modulation. This has a low data rate, but it’s very reliable; every bit is transmitted as a chirp – a linearly rising radio tone – and the data is encoded in the chirp’s starting frequency. To decode this, the receiver multiplies it with an inverse chirp, then takes a fast Fourier transform, revealing the starting frequency. This process has an equivalent gain of 24 dB, which is enough to let it decode signals even below the receiver’s noise floor.

The hardware [Stan] designed to implement this was comparatively simple, just an ESP32 microcontroller, an SX1281 radio chip, and a few peripherals. All four receivers worked in 2.4 GHz, but two had additional 900 MHz antennas. Against RF design convention, one of the receivers used a via to connect the antenna. This would normally cause a significant impedance mismatch, but since there were enough ground-plane vias nearby, the current return path was barely affected; the receiver’s performance hardly changed. In one test, all four receivers maintained a connection at more than five kilometers, despite a forest blocking the signal’s path.

We previously covered ExpressLRS when it was still an emerging technology. To get this kind of range, it builds on LoRa technology, which has reached some impressive distance records.

Thanks to [Keith Olson] for the tip!

Robot Chess But Each Piece Is A Small Robot

June 13, 2026 by Maya Posch 2 Comments

A topless chess piece. (Credit: 3DprintedLife, YouTube)

We have seen a number of self-playing chess boards over the years, but the general theme has been standard chess pieces moved by either an internal electromagnet or an external robotic arm. This is, of course, a reasonable choice, as it reduces complexity, and sometimes you can even use standard chess pieces on a regular board. But what if each piece could move by itself? That seems cooler, so that’s what [3DprintedLife] did with 3D-printed chess pieces that are also tiny robots.

Although technically not the first, as you can buy the commercial Chessnut Move offering, this being an open hardware and source project makes it a lot more interesting, also because the general design is generic enough to be usable for applications other than just playing chess.

The MiniBots, as the individual pieces are called, are built around a custom PCB with an ESP32-C3 module, two PMO8-2 miniature stepper motors with requisite drivers, a magnetometer, and are powered by a 170 mAh LiPo battery. Communication with the central hub is done using ESP-NOW, with each MiniBot using its own dedicated channel.

This hub’s mainboard also runs on an ESP32-C3 for the wireless interface, while the processing is handled via a serial link with a Raspberry Pi SBC that runs the main Python-based software. Localizing the individual pieces on the board is done by scanning electromagnets embedded in the board and using the readings from the individual magnetometers to triangulate the positions.

Although at the end of the video a basic prototype sort of works, the ESP32-C3, being a single-core MCU, tripped up the firmware, necessitating some changes that should be in the next update, along with power saving and easier recharging being issues to address.

If you want to see a more conventional chess robot, we’ve seen plenty.

Continue reading “Robot Chess But Each Piece Is A Small Robot” →

Investigating The S3 Virge’s Reputation As A 3D Decelerator Card

June 5, 2026 by Maya Posch 5 Comments

The special 512x384 mode with S3 card installed. (Credit: Bits und Bolts, YouTube) — The special 512×384 mode with S3 card installed. (Credit: Bits und Bolts, YouTube)

Back in 1996 the 3D gaming market on PC was beginning to heat up, with hot new titles like Tomb Raider coming out that year and requiring much more graphics power than what was needed for old titles like Doom and Duke Nukem 3D to experience good graphics. Thus you had to pick some kind of 3D accelerator card to buy. Here a common joke was that of the available options, the S3 Virge GPU was so bad that it was actually worse than running in software rendering, but was this true? Cue [Bits und Bolts]’s investigation to finally put this myth to rest.

On software rendering mode a zippy Pentium 166 would struggle to render at 640×480 resolution, so if you wanted more than 320×240, or really knock down graphical fidelity, you had to get that 3D accelerator card. After combining a P166 with an S3 Virge/DX – a minor update to the original Virge – the Tomb Raider game was first compared while running in 512×384 resolution, which the game offers you with an S3 card installed along with bilinear filtering.

After hitting a capped 30 FPS on that first test, 640×480 was tried and hit a solid 15 FPS with bilinear filtering enabled, but the conclusion is basically that the special 512×384 resolution mode is pretty good. Perhaps the main causes of the myth was the wide variability in quality of the various GPUs using the S3 Virge chip, as well as trying to run at anything other than this special resolution which appears to target the card’s strengths.

Continue reading “Investigating The S3 Virge’s Reputation As A 3D Decelerator Card” →

Tracing Olfactory Receptor Mapping Between The Nose And Brain

May 10, 2026 by Maya Posch 3 Comments

The way that the sense of smell works is that olfactory sensory neurons (OSNs) are wired up to olfactory receptors (ORs) in the nasal epithelium, from which they send signals to the brain. Once arrived there, a hierarchy of processing results in us experiencing the sensation of ‘smelling’. Exactly how the olfactory receptor-to-brain mapping works during development, and whether its physical pattern in the nasal epithelium is replicated in the brain, remained major questions until now. In a study published in Cell by [David H. Brann] and others, many of these questions have now been answered, at least for mice.

As it turns out, the mapping between OSNs and ORs isn’t performed by a random selection process, but instead creates a receptor map that’s closely matched between the nasal epithelium and the brain. What has complicated answering this question up till now is that the nasal epithelium isn’t a flat surface, but a convoluted labyrinth that maximizes surface area to smell better.

The second issue was linking the physical location of OSNs and gene expression in the nasal epithelium. Using a new approach, the researchers showed an intricate patterning in this epithelium, with the basal stem cells from which it regenerates maintaining this patterning. This makes for a system very similar to, for example, the auditory system, where the detection of frequencies in the inner ear, as a linear system, is found to be replicated in the brain.

Although it does not provide us with all the answers yet about how this genetic patterning works, it offers a glimpse at a fascinating system that would seem to be used repeatedly across sensory systems. It may also provide potential treatments for medical conditions affecting the olfactory system, whereby the sense of smell is missing, reduced, or oddly miswired, for example, after a SARS-CoV-2 infection of the olfactory nerve that leads to symptoms such as a constant sensation of a burning smell.

You have to wonder if a better understanding of the nose will revive interest in digitally creating and sending smells?

Exposing A Radiation-Hardened 2.4 GHz Wi-Fi Receiver To 500 Kilograys

April 4, 2026 by Maya Posch 5 Comments

From outer space to down here on Earth, there are many places where ionizing radiation levels are high enough that they effectively bar access for humans, but also make life miserable for anything containing semiconductor technology. This is especially true for anything involving wireless communications, such as Wi-Fi. However, recently Japanese researchers have created a Wi-Fi chip that is claimed to be so radiation-hardened that it can be used even in gamma ray-rich environments, such as in the worst contaminated depths of the Fukushima Daiichi nuclear reactor.

The indicated dose exposure of 500 kilograys that the chip survived during testing is quite significant. A single gray (Gy) is the absorption of one joule of energy per kilogram of matter. In radiation therapy, a solid epithelial tumor can receive as much as 60 to 80 Gy in a single dose, for example.

Continue reading “Exposing A Radiation-Hardened 2.4 GHz Wi-Fi Receiver To 500 Kilograys” →

Clean Enclosures, No Printing Necessary

March 29, 2026 by Tyler August 52 Comments

Unless you’re into circuit sculptures, generally speaking, a working circuit isn’t the end-point of a lot of electronics projects. To protect your new creation from grabby hands, curious paws, and the ravages of nature, you’ll probably want some kind of enclosure. These days a lot of us would probably run it off on the 3D printer, but some people would rather stay electronics hobbiests without getting into the 3D printing hobby. For those people, [mircemk] shares how he creates professonal-looking enclosures with handtools.

The name [mircemk] will seem familiar to longtime readers– we’ve featured many of his projects, and they’ve always stood out for the simple but elegant enclosures he uses. The secret, it turns out, is thin PVC sheeting from a sign shop. At thicknesses up to and including 5 mm, the material can be bent by hand and cut with hobby knives. It’s obviously also amenable to drilling and cutting with woodworking tools as well. Drilling is especially useful to make holes for indicator LEDs. [mircemk] recommends ~~cyanoacrylate~~ universal glue to hold pieces together. For holding down the PCB, the suggestion of double-sided tape will work for components that won’t get too hot.

Rather than paint, the bold contrasting colours we’ve become used to are applied using peel-and-stick wallpaper, which is a great idea. It’s quick, zero mess, and the colour is guaranteed to be evenly applied. It might even help hold the PVC enclosure together ever so slightly. You can watch him do it in the video embedded below.

We hate to say it, but for a one-off project, this technique probably does beat a 3D printed box for professional looks, assuming you have [mircemk]’s motorskills. If you don’t have said motor skills, check out this parametric project box generator. If you’d rather avoid PVC while making a square box to hold a PCB, have you considered using PCBs?

Thanks to [mircemk] for the tip! If you have a tip or technique you want to share, please box it up and send it to the tipsline

Continue reading “Clean Enclosures, No Printing Necessary” →