computer hacks

1344 Articles

computer hacks

Soviet ZX Spectrum clone on a table

ZX Spectrum, Soviet Style: A 44-IC Clone You Can Build

March 10, 2025 by 12 Comments

If you’ve ever fancied building a ZX Spectrum clone without hunting down ancient ULAs or soldering your way through 60+ chips, [Alex J. Lowry] has just dropped an exciting build. He has recreated the Leningrad-1, a Soviet-built Spectrum clone from 1988, with a refreshingly low component count: 44 off-the-shelf ICs, as he wrote us. That’s less than many modern clones like the Superfo Harlequin, yet without resorting to programmable logic. All schematics, Gerbers, and KiCad files are open-source, listed at the bottom of [Alex]’ build log.

The original Leningrad-1 was designed by Sergey Zonov during the late Soviet era, when cloning Western tech was less about piracy and more about survival. Zonov’s design nailed a sweet spot between affordability and usability, with enough compatibility to run 90-95% of Spectrum software. [Alex]’ replica preserves that spirit, with a few 21st-century tweaks for builders: silkscreened component values, clever PCB stacking with nylon standoffs, and a DIY-friendly mechanical keyboard hack using transparent keycaps.

While Revision 0 still has some quirks – no SCART color output yet, occasional flickering borders with AY sound – [Alex] is planning for further improvements. Inspired to build your own? Read [Alex]’ full project log here.

A plugged-in 12VHPWR cable, with two thermistors inserted into the connector shell, monitoring for heat

12VHPWR Watchdog Protects You From Nvidia Fires

March 3, 2025 by 72 Comments

The 12VHPWR connector is a hot topic once again – Nvidia has really let us down on this one. New 5080 and 500 GPUs come with this connector, and they’re once again fire-prone. Well, what if you’re stuck with a newly-built 5080, unwilling to give it up, still hoping to play the newest games or run LLMs locally? [Timo Birnschein] has a simple watchdog solution for you, and it’s super easy to build.

All it takes is an Arduino, three resistors, and three thermistors. Place the thermistors onto the connector’s problematic spots, download the companion software from GitHub, and plug the Arduino into your PC. If a temperature anomaly is detected, like one of the thermistors approaching 100C, the Arduino will simply shut down your PC. The software also includes a tray icon, temperature graphing, and stability features.  All is open-source — breadboard it, flash it. You can even add more thermistors to the mix if you’d like!

This hack certainly doesn’t just help protect you from Nvidia’s latest creation – it can help you watch over any sort of potentially hot mod, and it’s very easy to build. Want to watch over connectors on your 3D printer? Build one of these! We’ve seen 12VHPWR have plenty of problems in the past on Nvidia’s cards – it looks like there are quite a few lessons Nvidia is yet to learn.

SHOUT For Smaller QR Codes

February 26, 2025 by 19 Comments

QR codes have been with us for a long time now, and after passing through their Gardenesque hype cycle of inappropriate usage, have now settled down to be an important and ubiquitous part of life. If you have ever made a QR code you’ll know all about trying to generate the most compact and easily-scannable one you can, and for that [Terence Eden] is here with an interesting quirk. Upper-case text produces smaller codes than lower-case.

His post takes us on a journey into the encoding of QR codes, not in terms of their optical pattern generation, but instead the bit stream they contain. There are different modes to denote different types of payload, and in his two examples of the same URL in upper- and lower- cases, the modes are different. Upper-case is encoded as alphanumeric, while lower-case, seemingly though also containing alphanumeric information, is encoded as bytes.

To understand why, it’s necessary to consider the QR codes’ need for efficiency, which led its designers to reduce their character set as far as possible and only define uppercase letters in their alphanumeric set. The upper-case payload is thus encoded using less bits per character than the lower-case one, which is encoded as 8-bit bytes. A satisfying explanation for a puzzle in plain sight.

Hungry for more QR hackery? This one contains more than one payload!

Giving A Proprietary Power Supply The Boot

February 2, 2025 by 29 Comments

You’ve probably noticed that everywhere you go — the doctor’s office, hotels, or retail shops, there are tiny PCs everywhere. These small PCs often show up on the surplus market for a very good price, but they aren’t quite full-blown PCs. They usually have little option for expansion and are made to be cheap and small. That means many of them have custom and anemic power supplies. We aren’t sure if [bm_00] needed a regular power supply to handle a graphics card or if the original power supply died, but either way, the HP small-form-factor box needed a new power supply. It took some clever work to be able to use a normal power supply in the little box.

At first, we thought this wouldn’t be much of a story. The motherboard surely took all the regular pins, so it would just be a matter of making an adapter, right? Apparently not. The computers run totally on 12V and the motherboard handles things like turning the computer on and off. The computer also was trying to run the power supply’s fan which needed some work arounds.

Continue reading “Giving A Proprietary Power Supply The Boot” →

A Modem As A Cassette Interface

January 24, 2025 by 20 Comments

At least some in the audience will at some time in the distant past have loaded or saved a program on cassette, with an 8-bit home computer. The machine would encode binary as a series of tones which could be recorded to the tape and then later retrieved. If you consider the last sentence you’ll quickly realize that it’s not too far away from what a modem does, so can a modem record to cassette and decode it back afterwards? [Jesse T] set out to give it a try, and as it turns out, yes you can.

The modem talks and listens to the cassette recorder via circuitry that provides some signal conditioning and amplification, as well as making a dial tone such that the modem thinks it’s talking to a real phone line. An Arduino steps in as dial tone creator.

Of course, this is hardly a viable solution to 21st century data storage need, but that’s hardly the point as it’s a cool hack. We like it, and oddly we’ve seen a similar technique used with a retrocomputer in the past.

Continue reading “A Modem As A Cassette Interface” →

This Home Made Laptop Raises The Bar

January 23, 2025 by 54 Comments

With ready availability of single board computers, displays, keyboards, power packs, and other hardware, a home-made laptop is now a project within most people’s reach. Some laptop projects definitely veer towards being cyberdecks while others take a more conventional path, but we’ve rarely seen one as professional looking as [Byran Huang]’s anyon_e open source laptop. It really takes the art to the next level.

The quality is immediately apparent in the custom CNC-machined anodised aluminium case, and upon opening it up the curious user could be forgiven for thinking they had a stylish commercial machine in their hands. There’s a slimline mechanical keyboard and a glass trackpad, and that display is an OLED. In fact the whole thing had been built from scratch, and inside is an RK3588 SoC on a module sitting on a custom-designed motherboard. It required some effort for it to drive the display, a process we’ve seen cause pain to other designers, but otherwise it runs Debian. The batteries are slimline pouch cells, with a custom controller board driven by an ESP32.

This must have cost quite a bit to build, but it’s something anyone can have a go at for themselves as everything is in a GitHub repository. Purists might ask for open source silicon at its heart to make it truly open source, but considering what he’s done we’ll take this. It’s not the first high quality laptop project we’ve seen by any means, but it may be the first that wouldn’t raise any eyebrows in the boardroom. Take a look at the video below the break.

Continue reading “This Home Made Laptop Raises The Bar” →

Going Minimal: 64×4, The Fun In Functional Computing

January 22, 2025 by 38 Comments

If you’ve ever wondered what makes a computer tick, the Minimal 64×4 by [Slu4] is bound to grab your attention. It’s not a modern powerhouse, but a thoughtfully crafted throwback to the essence of computing. With just 61 logic ICs, VGA output, PS/2 input, and SSD storage, this DIY wonder packs four times the processing power of a Commodore 64.

What sets [Slu4]’s efforts apart is his refusal to follow the beaten track of CPU development. He imposes strict complexity limits on his designs, sticking to an ultra-minimalist Von Neumann architecture. His journey began with the ‘Minimal Ur-CPU’, a logic-chip-based computer that could crunch numbers but little else. Next came the ‘Minimal 64’, featuring VGA graphics and Space Invaders-level performance. The latest ‘Minimal 64×4’ takes it further, adding incredible speed while keeping the design so simple it’s almost ridiculous. It’s computing stripped to its rawest form—no fancy sound, no dazzling graphics, just raw resourcefulness.

For enthusiasts of retro-tech and DIY builds, this project is a treasure trove. From text editors to starfield simulations to Sokoban, [Slu4] proves you don’t need complexity to make magic. Continue reading “Going Minimal: 64×4, The Fun In Functional Computing” →