A small, orange 3D printer is shown on a desk with a filament dry box. The printer is printing a waving cat figurine. The printer is a CoreXY configuration, and the side panels are 3D-printed orange plastic.

3D Printing A Miniature CoreXY Printer

Although no longer so common as during the heyday of the RepRap movement, it’s easier than ever to build your own largely-printed 3D printer, with designs such as Voron’s delivering excellent quality. Nevertheless, there are still niches to be filled by new designs, such as [Alex Yu]’s mostly-printed Encore design.

The Encore uses CoreXY kinematics and linear rails for the X and Y axes. Its has no internal frame; the linear rails are mounted directly to the side panels, which were printed but provided sufficient rigidity. The printer is modular, and all the parts are designed to fit within a 225 mm print bed. The Encore itself uses a 120 mm bed, a Bowden extruder, and a lightweight Bambu-style hotend. The drive motors are NEMA 17 stepper motors, and they use sliding mounts for belt tensioning. The power supply sits behind the rods supporting the Z axis, and the controller board is in the base of the printer.

Building the printer was simple; tuning it, less so. The combination of a Bambu-type hotend with a Bowden extruder created some complications, and the hotend initially received too little cooling. [Alex] solved the cooling issues by using a stronger fan on the hotend, redesigning the ventilation shroud, and adding two inward-blowing fans along the sides of the build volume. After correcting some issues with Z-axis stability, the Encore produced some quite good-looking parts. [Alex] is still improving and documenting some aspects of the printer, but he’s uploaded his progress so far to GitHub.

We’ve seen some mostly-printed printers before, including a high-speed printer, one which printed all structural components, and one which was entirely 3D printed.

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An Unlikely Host For An 8080 Emulator

To emulate vintage microprocessor hardware, it’s normal to find a modern host that provides alongside the number-crunching grunt, sufficient physical connections to interface with its support hardware. Thus if you were shopping around it might be reasonable to pick something with a powerful core and plenty of pins. Yet to emulate an 8080, [Ted Fried] has eschewed both of these — opting for an ATtiny85, a microcontroller deficient in both pins and processing power.

This seemingly impossible feat is achieved by reducing the physical connection to an SPI bus and offloading the support functions to a Teensy. The emulation code is significantly optimized C, and includes a 128 byte cache to speed up matters. This delivers a speed claimed to be only very slightly slower than a real 8080 when booting CP/M, which is quite a feat.

We’re sure that CP/M enthusiasts will have fun with this project, and we especially like the full write-up. Going to the effort of making fake 1975 electronics magazine covers for the project really is going the extra mile, and we appreciate that. Meanwhile if you’d like one of your own, the whole thing can be found in a GitHub project.

If you’re not familiar with the 8080, maybe we can get you started.

Using Brand New NiMH Cells After Sitting 12 Years Unused

You know your batteries are old when their labels have faded. (Credit: DiodeGoneWild, YouTube)
You know your batteries are old when their labels have faded. (Credit: DiodeGoneWild, YouTube)

After finding a pack of NiMH rechargeable cells that had never been used since buying them in 2014, [DiodeGoneWild] decided to test whether they could be tossed or not. After previously testing different brand cells that had gone high internal resistance after only about five years, he wasn’t expecting much. Amazingly, the batteries not only recovered, but seems to be not that much worse off for wear.

Three of the four precharged cells still held some voltage and happily charged back up to their rated 2,000 mAh capacity basically with the first cycle. One of them read 0V initially, but was revived using the typical manual charging approach involving a bench power supply. After a few charge-discharge cycles only the deep discharged cell showed some noticeable degradation with slightly reduced capacity, but all of them read healthy internal resistance values.

What this mostly shows is that not all NiMH cells are made the same, with the Tronic ones that previously failed after a few years doing much worse than these Activ Energy cells which are apparently sold primarily at Aldi stores. Overall NiMH is a pretty robust battery chemistry, so it’s always worth it to try reviving a cell before tossing it.

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

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.

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Over-Engineering An FDM Spool Holder From Prusa Mk4S Remains

Unlike resin printers where you generally just pour the fresh resin into the easily accessible vat, FDM printers need to squirrel away at least one spool and its requisite holder somewhere. For bed slingers this generally means a top-mounted spool holder, while for CoreXY enclosed printers they can appear on the sides, top or – inexplicably – on the back. While a side-mounted spool is often convenient, access to the side can still be blocked, in which case you do what [3D Maker Noob] did and over-engineer a fancy top-mounted spool holder.

The problem started after converting a Prusa Mk4S to a Core One using the conversion kit, which changes the position of the spool, forcing him to work around not having access to the right side of the machine where the default position is. After a first version using many of the left-over parts of the original Mk4S to create a fancy box-shaped spool holder, he proceeded to upgrade it as detailed in the video. All project files and instructions are available on Printables.

The result is a box you stack on top of the printer somewhat like a multi-spool box, just flatter and with a flippy lid on the front from which a rail slides out with the magnetically attached spool holder. A spool holder which you naturally can further customize to fit different spools. Even if over-engineered, you can’t deny that it would fit in confined spaces and looks pretty good while doing its job.

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As It Turns Out, There’s More Than One Cassette Mechanism Being Made After All

It’s become an accepted truth amongst tapeheads that there’s no point looking at new hardware, because there’s only one tape mechanism being made anywhere in the world anymore, and that it sucks. [VWestlife] may enjoy German automobiles, based on the name, but he’s also a tapehead– and he took the time to demonstrate on YouTube that the accepted truth just ain’t so.

The supposed One Mechanism to Rule Them All in Lo-Fi is designed or made by Chinese company Tanishin. Certainly Tanishin does make a tape mechanism, but as [VWestlife] demonstrates with a few teardowns, there’s absolutely more than one on the market. That doesn’t mean any of the new offerings will out-compete your vintage Sony Walkman, but it does mean there are differences worth considering if you were to buy new.

Note that it is handhelds like the Walkman being talked about– it must be, since there are both slot-loading and flip-loading decks still being made, and even if you’re not a tapehead you should be able to tell that those won’t share the same part on the BOM.

With a few teardowns, he finds three separate mechanisms, followed by a deep-dive into the Tanishin. If you’re looking to buy a new walkman– or perhaps use its guts to build a mass storage device-– you might want to watch the whole thing to help you pick. On the other hand, the mechanism doesn’t matter that much, as he points out. It brings the tape over the head, but that’s not difficult. Everything else– from the motor that needs to draw the tape out evenly, to the pickup and the preamps and amplifiers–is where noise and poor quality sound tends to creep in, especially when something’s built to a budget.

Overall, [VWestlife] takes pains to point out that these ‘crappy’ new players aren’t any worse than the original Sony Walkman– we’ve just been spoiled by decades of better media than the humble compact cassette. That’s no slight against the cassette– people are still pushing its limits to this day, like this insanely fast vacuum-driven mechanism we featured.

Thanks to [Stephen Walters] for the tip!

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Using Windows 11 On An LGA 775 PC With AGP Videocard

Although the thought of installing a modern operating system like Windows 11 on something as archaic as a Core 2 Quad Q6600 Intel CPU may seem ridiculous, it being the flagship CPU of the time means that it still chews up low-end Celeron systems that are on the supported hardware list like the N4020. Hence [Omores] commencing on this latest adventure, with the snag being that the chosen mainboard features an AGP bus that Windows 11 no longer supports.

A GPU box from the related HD 4670 PCIe card, not the used HD 4650 AGP card with 1 GB of DDR2. (Credit: Omores, YouTube)
A GPU box from the related HD 4670 PCIe card, not the used HD 4650 AGP card with 1 GB of DDR2.

This system is intended to multi-boot a range of Windows OSes starting with Windows 98, while also playing nice with DOS and even Windows 11. In addition to the quad-core, 2.4 GHz Q6600 there’s also an amazing 3 GB of DDR1 RAM in the system.

The mainboard is the 2003-era Asrock 865PE, with the GPU being the highest-end GPU that still came in AGP flavor: the Radeon HD 4650 from 2009. Since the sole reason that Windows 11 doesn’t support AGP any more is due to the supporting files not being included with Windows 11, hence you can track it down on a Windows 10 1507 release install – such as the Intel AGP440.sys driver here – and install them with some file editing.

Since Windows 11 still supports the WDDM driver model from Windows Vista and 7 you can then install the Catalyst drivers from 2012 and be up and running. You only get 1 GB of VRAM for this card, but you probably don’t need much more on this level of hardware.

One major stumbling block remains, however, as Windows 11 24H2 enforces SSE4.2 instructions which the CPU doesn’t support. Ergo 23H2 is the newest Windows 11 version that can run on this system, with only the Education and Enterprise still receiving security updates, making it a bit of a pyrrhic victory, especially as Windows 7 benchmarks a fair bit faster on the same hardware.

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