Back in 2019 we first came across the mutantC, an open source 3D printable Raspberry Pi handheld created by [rahmanshaber] that took more than a little inspiration from Sony’s VAIO ultra-mobile PCs (UMPCs) from the early 2000s. It was an impressive first effort, but it clearly had a long way to go before it could really be a practical mobile device.
Well after two years of development and three iterative versions of this Linux powered QWERTY slider, [rahmanshaber] is ready to show off the new and improved mutantC_v4. Outwardly it looks quite similar to the original version, with the notable addition of a tiny thumbstick and a pair of programmable buttons on the right side that can be used for input in addition to the touch screen. But inside it’s a whole other story, with so many changes and improvements that we hardly even know where to start.
Probably the most notable improvement is the addition of an ESP32-S2, specifically a bare ESP-12K module, to the main PCB. Previous versions of the hardware used an Arduino Pro Micro to interface with all the hardware, but the added horsepower of the ESP32 should come in handy with the array of sensors, controls, and NeoPixels that [rahmanshaber] has tasked the chip with. There’s even a buzzer and a coin-style vibration motor in there to provide some feedback to the user. While the board has changed significantly, it still retains compatibility with the Pi Zero, 2, 3, and 4.
Another notable addition is the expansion connector on the bottom of the handheld that has pins for I2C, UART, and 3.3 V. In the video below, [rahmanshaber] mentions that this feature was previously implemented with a standard 2×6 female header block, but is now using a far slimmer female USB-C port. We do wonder if it’s not a bit confusing to have this faux-USB port right next to the real one that’s actually used to charge the system, but with such cramped quarters occasionally you’ve got to make some tough decisions like that.
While there’s nothing quite like running retro games on their original hardware, using older consoles in today’s day and age can be a hassle due to incompatibilities with modern chargers and headphones. [tito] and [kyle] worked together to update Nintendo’s Game Boy Advance SP with a whole bunch of new features, tightly packed inside a 3D-printed replacement backshell. (Video, embedded below.)
The original 600 mAh battery has been replaced with a 1600 mAh pack for several hours of additional screen time. A Qi standard wireless power module as well as a USB-C connector allows charging the battery without carrying the original mains adapter. A Bluetooth module enables the use of wireless headphones, and a 3.5 mm jack enables classic earbuds as well, a feature lost when the SP replaced the original GBA.
The new backshell fits exactly on the original console, making it about 10 mm thicker. Although this makes it slightly less portable, it is apparently more comfortable to hold for those with big hands. The new functionality is implemented using off-the-shelf circuit boards, connected together with flying wires that are soldered to the required points on the GBA’s circuit board. The original connectors and switches remain in place and functional, and the entire operation can be undone if you want to return the device to its original state.
Others have added USB charging to the original GBA, or even stretched that handheld to become twice as wide. But adding significant new functionality previously required replacing the handheld’s entire contents.
Starting with a working Game Boy Advance and a donor one with a busted motherboard, the frankenstein-ification could start. A Dremel split one case in half and removed the sides on another, while trusty old car body filler helps fill and smooth the gaps. A particularly clever trick is to use the Dremel to create channels for the filler to adhere easier. Several areas had to be built up with filler and glued in bits of plastic as a base. As you can see in the video below, the countless hours of sanding, priming, sanding, and more priming led to a beautifully smooth finish. The choice of purple paint really sells the impression of a factory-fresh Game Boy Advance.
The working circuit board was desoldered and the donor board was cut into pieces to fit in the extended sides. Using some magnet wire, connections were bridged over to the original motherboard via the test points on the PCB. [Elliot] didn’t opt to swap the screen to an IPS display or add a backlight. These quality of life improvements are nice, but a dead giveaway that Nintendo didn’t make it. The goal is to get the user to wonder, even if just for a second, what if Nintendo just happened to make this wide one-off handheld console.
[Elliot] made it simply because he found it interesting and enjoyed the form of the thing he made. Is it a hack? Is it art? Probably a little bit of both. This isn’t his first modified Nintendo handheld either. He previously made a long Nintendo Gameboy DMG-01. We love seeing all the wild hacks and tweaks made to Game Boy line, such as this Game Boy Color inside the DMG-01.
Over the years we’ve seen plenty of homebrew handheld game systems that combine an AVR microcontroller, a few buttons, and an small OLED display. Some of them have even been turned into commercial products, such as the Arduboy. They’re simple, cheap, and with the right software, a lot of fun. But being based on an MCU, most of them share the same limitation of only being able to hold a single game at any one time.
With the microcontroller on the cartridge, the only hardware that stays behind on the Game Card is the SSD1306 128×64 OLED display, buttons, and the battery. That means the handheld is effectively non-functional unless a game is slotted in, but that could be said of most early cartridge-based game systems as well. On the other hand, it also opens up the possibility of producing cartridges with more powerful microcontrollers down the line.
It’s easy to take for granted the constantly-connected, GPS-equipped, navigation device most of us now carry in our pockets. Want to know how to get to that new restaurant you heard about? A few quick taps in Google Maps, and the optimal route given your chosen transportation method will be calculated in seconds. But if you ever find yourself lost in the woods, you might be in for a rude awakening. With no cell signal and a rapidly dwindling battery, that fancy smartphone can quickly end up being about as useful as a rock.
Enter the IndiaNavi, a modernization of the classic paper map that’s specifically designed to avoid the pitfalls that keeps your garden variety smartphone from being a reliable bushcraft tool. The color electronic paper display not only keeps the energy consumption low, but has unbeatable daylight readability. No signal? No problem, as the relevant maps are pre-loaded on the device.
Besides the 5.65 inch e-paper display from Waveshare, the India Navi features a L96 M33 GPS receiver and ESP32-WROOM-32 microcontroller. The 3D printed enclosure that holds the electronics and the lithium pouch battery that powers them is still in the early stages, but we like the book-style design. The focus on simplicity and reliability doesn’t end with the hardware, either. The software is about a straightforward as it gets: just boot the IndiaNavi and you’re presented with a map that shows your current position.
We’ve seen a huge influx of bespoke portable computers over the last couple of years thanks to availability of increasingly powerful single-board computers. The vast majority of these have been ARM powered using something like the Raspberry Pi 4, and naturally, run Linux. Only a handful have run on x86 hardware, usually because whoever built it wanted to be able to run Windows.
But this handheld x86 Hackintosh running the latest Mac OS on the LattePanda Alpha is truly something unique. Creator [iketsj] claims it to be a world’s first, and after a bit of searching, we’re inclined to agree. While others have installed Mac OS on the LattePanda to create Hackintosh laptops, this would indeed appear to be the first handheld computer to utilize this particular hardware and software blend.
Like other custom portables we’be seen, this one starts with a 3D printed enclosure. The overall design reminds us a bit of the YARH.IO we covered last year, and even borrows the trick of reusing the membrane and PCB of one of those miniature keyboard/pointer combos. Which in this case ends up being especially important, as in keeping with Apple’s own portable Mac OS machines, the screen on this handheld doesn’t support touch.
We especially like how the integrated Arduino on the LattePanda is being used in conjunction with some MOSFETs to control power to the handheld’s LCD, keyboard, and fans. While it sounds like the fans are currently running at full throttle, [iketsj] mentions he does intend on adding automatic speed control in the future. A dedicated “chassis controller” like this makes a lot of sense, and is something we imagine will only become more common as these portable builds become increasingly complex.
Why reach for a bland, commercially available calculator when you be using a model that employs RPN (Reverse Polish Notation) in its calculations and be a custom build all at the same time? The kids may have colour TFTs and graphing functions, but your keyboard has no equals sign, and that means something.
Unfortunately for RPN enthusiasts, the RPN calculator is a little on the rare side. Since classic models from the 1970s and ’80s are rather pricey, [Anton Poluektov]’s just build his own called the OpenCalc. This glorious specimen is an open hardware RPN calculator with more than a nod to the venerable Hewlett Packard HP42 in its design.
At its heart is an STM32L476 low-power ARM processor and a Sharp Memory LCD, all on a PCB clad in a 3D-printed case you’d have been proud to own in the 1980s. It runs from a CR2032 which is more than can be said for some modern styles of calculator, and it gives the user everything you could wish for in a scientific calculator. The key legends are a set of printable stickers, which when printed on self-adhesive laser film prove durable enough to last. All the resources can be found in a GitHub repository, so if RPN is your thing there’s nothing to stop you building one for yourself.