Author: Matt Varian

76 Articles

Open-Source eink firmware

Pocket-Sized E-Ink Gets A Firmware Upgrade

April 5, 2026 by 18 Comments

Not so long ago, e-ink devices were rare and fairly pricey. As they have become more common and cheaper, some cool form-factor devices have emerged that suffer from subpar software. [Concretedog] picked up just such a device, and that purchase led to the discovery of a cool open-source firmware project for this tiny gadget.

[Concretedog] described the process of loading the firmware, which is just about as easy a modification as one can make. You plug the e-ink display into your computer, visit a website, and can flash it right from there. Once the display is running the CrossPoint Reader firmware, it unlocks some new tricks on this affordable reader. The firmware lets you turn the device into a WiFi hotspot and upload books wirelessly, or it can connect to an existing network to add files that way. It also enables rotating the display and KOReader syncing if you have multiple devices you read from.

We love seeing the community step in and improve devices that are hardware-wise good, sometimes great, but come up lacking in the software or firmware department. Thanks [Concretedog] for sharing your experience with this device and the cool open-source firmware. Be sure to check out some other projects we’ve featured where a firmware swap breathed new life into the hardware.

macro photo slider

Tiny Moves, Big Depth: An Open-Source Macro Focus Slider

April 5, 2026 by 7 Comments

When taking macro photographs, you often need just a tiny bit of controlled motion — so little that it’s tough to pull off by hand. To address this, [Salveo] designed a small open-source macro photography slider featuring an anti-backlash handle.

Macro photography gives you an extremely shallow field of view, sometimes under 1 mm of depth, in which subjects stay in focus. To combat this, it’s common to capture multiple images while sliding the camera forward or backward, then combine them for a much larger depth of field than a single shot provides. [Salveo]’s slider gives fine control over this focus-stacking process, with the knob even marked to show every 1 mm of linear travel.

The slider is built around a 150 mm linear rail, though it could easily be lengthened or shortened to suit your needs. A T8 leadscrew, paired with anti-backlash nuts, translates the knob’s rotation into smooth linear motion. The knob itself uses a custom-designed anti-backlash mechanism to ensure the slider works cleanly in either direction.

You can grab all the 3D-printable files as well as the full bill of materials from the project page. Be sure to check out [Salveo]’s build video below. Thanks [Tim L.] for sending in this awesome open-source slider. Be sure to check out some of the other macro photography projects we’ve covered, too.

Continue reading “Tiny Moves, Big Depth: An Open-Source Macro Focus Slider” →

Dotterboard smt counter

Tame The Tape: Open-Source Dotterboard For Bulk SMT Parts

March 30, 2026 by 9 Comments

One of the great things about building electronics today is how affordable SMT components have become — sometimes just fractions of a cent each. That low price often means ordering far more than you need so you’ll have spares on hand the next time a project calls for them. Keeping track of exactly how many of each part you actually have, though, is rarely easy. To solve that problem, [John] built the Dotterboard, an open-source SMT tape counter.

While working on some of his other projects, [John] found himself managing thousands of tiny SMT parts and decided it was time to automate the counting. The Dotterboard takes inspiration from the BeanCounter — a compact, portable SMT tape counter — but expands the design to handle larger components beyond the 8 mm tapes the BeanCounter targets.

The Dotterboard is mostly 3D-printed and uses just a few common hardware parts such as springs and ball bearings. An OLED displays the current count, which comes from an encoder tracking movement and multiplying by the number of components per hole. At the heart sits an RP2040 Zero that needs nothing more than a single USB-C cable for power, unlike the bulky industrial SMT counters that demand AC outlets and desk space.

Be sure to check out all the details of the build on [John]’s website, and grab the files from his GitHub if you want to make your own. Let us know what are some projects you’ve done to save you the headache of doing the same task by hand for hours on end.

Continue reading “Tame The Tape: Open-Source Dotterboard For Bulk SMT Parts” →

pi 1990s brick phone

No More Paperweight: This Vintage Brick Phone Is Back Online

March 13, 2026 by 20 Comments

Remember those brick cellphones in the 1990s? They were comically large by today’s standards. These phones used the 1G network to communicate and, as such, have been unusable for decades now. However [Alan Boris] has resurrected this classic phone to operate today.

Originally costing as much as today’s top-of-the-line phones, but instead of weighing just a few ounces this classic Motorola DynaTAC 8000 Classic 2 tips the scales at a hefty 1.5 lbs. [Alan Boris] decided to not just bring the electronics back to life, but to even stuff a modern cellphone inside it to make it fully functional. Given the size of this phone, finding room for the new innards wasn’t much of a challenge. In fact, after the retrofit there was less in the phone than when it started life.

Using a perfboard and some tactile switches he was able to sense the button presses on the phone’s keypad and relay those to a Raspberry Pi Pico 2. The Pico in turn drove a small color LCD to replicate the original screen and controlled a pair of ADG729 boards used to dial the BM10 cellphone within this cellphone. The BM10 is a cellphone about the size of a 9V battery, making it easy to put inside the DynaTAC and bring the handset back to the modern cellular network.

Thanks [Alan Boris] for the tip! Be sure to check out our other cellphone hacks as well as some of our other retrofit hacks.

Continue reading “No More Paperweight: This Vintage Brick Phone Is Back Online” →

Mimisbrunnur

Calculator Case To Scratch-Built Pocket E-Reader

March 11, 2026 by 7 Comments

E-readers are an awesome creation allowing you to display digital information in a way that requires little battery life. While there’s plenty of very impressive models to chose from on the commercial market, it’s also possible to build one yourself — which is exactly what [kaos-69] did in his Mimisbrunnur project, creating a truly unique e-reader from scratch.

While looking through old junk at home, [kaos-69] came across a case that held a calculator and pen at one point in the distant past. The pen was gone and the calculator no longer functioned but the case held promise. He removed the calculator and got some parts on order. For the e-paper display he went with a 5.83-inch unit that just fit inside the spring-loaded case. The Mimisbrunnur is powered by a 2000 mAh LiPo battery, with a micro SD card reader for storing what will be displayed. The brains come from an RP2040 microcontroller on an Adafruit Feather breakout board, which worked out great as it already takes care of battery management and the 24-pin interface for the e-paper display.

There are also eight buttons that live below the display for user interface, and even some LEDs to aid in reading in the dark. The depth of the case allowed all this to be connected with the use of a perfboard and some risers to set the screen forward, allowing the battery to live behind it. Using the Mimisbrunnur is pretty straightforward with the eight buttons sitting below icons on the screen giving you clear guidance on how to turn the page, add a bookmark, or browse the SD card for another file to open.

We’ve seen some impressive DIY e-readers over the years, such as the dual-screen Diptyx and the Open Book. But this project is an excellent reminder that a device doesn’t have to be complex to get the job done.

6502 based laptop

Retro Rover: LT6502 Laptop Packs 8-Bit Power On The Go

February 17, 2026 by 9 Comments

Making your own laptop can be a challenging project, but a doable one, especially given the large number of options available today for computing. Of course nothing says you need to use a modern component in your build, and in the LT6502 project by [TechPaula] they didn’t go with a modern RPi or the like, nope went right back to about 50 years ago to use a 6502 at the heart of this DIY laptop build.

The 6502 is an 8-bit microprocessor from the 1970s, found in the Commodore 64 and Apple II. This wasn’t their first venture into 8 MHz world of the 6502, prior to this laptop build there was a desktop build the PC6502 bringing this chip of old into a PC/104 form factor. The LT6502 adds in the things you’d expect with a laptop, a 9-inch foldable screen, a 10,000 mAh battery, several external ports for things such as serial console and USB-C charging. A custom keyboard adds in low-profile switches as well as including a HDSP-style 8-character display, a great addition for a modern take on this vintage chip. Onboard there is 46 KB of RAM and with the addition of the CompactFlash for storage the LT6502 runs EhBASIC which we’ve seen before in some other great projects.

The case is mainly 3D-printed safely enclosing the custom PCBs for both the keyboard and motherboard, and providing a satisfying glow with the built-in LEDs within. All of the files are up on the project’s site so be sure to swing by and check out both this and the desktop PC/104 predecessor to it. Great job [TechPaula], looking forward to seeing the future installments on the LT6502 such as implementing the included internal expansion slot.

Toybox Tractor: Plywood, Lathe Hacks, And 350W Of Fun

February 5, 2026 by 14 Comments

When you think of a toy tractor, what probably comes to mind is something with fairly simple lines, maybe the iconic yellow and green, big rear tires, small front ones. Well, that’s exactly what [James] built, with simple, clean lines and a sturdy build that will hold up to driving around off-road in the garden. This Tractor is a great build, combining CAD, metal and wood work, some 3D printing, and electronics.

Starting at the power plant for the build, [James] went with a 350W DC motor powered by a 36V Li-ion battery from an e-bike. The motor turns a solid rear axle he made on a mini-lathe, connected to a set of riding lawn mower wheels. The mini-lathe spindle bore was too small to accommodate the shaft, and the lathe was not long enough to use the tailstock, so [James] had to get creative, using a vice and a piece of wood to make a stand–in tailstock, allowing him to turn this custom rear axle. The signature smoothly curved bonnet was made possible with plywood and body filler, rather than the sheet metal found on full-sized tractors. In fact, most of the build’s frame used plywood, giving it plenty of strength and, once painted, helping give it the appearance of a toy pulled out of a toybox.

This build had a bit of many domains in it, and all combined into a fantastic final result that no doubt will bring a smile to any face that gets to take the Tractor for a ride. Thanks [James] for documenting your build process, the hacks needed to pull off the tough bits along the way in making this fun toy. If you found this fun, be sure to check out another tractor related project.