PCB Pen Holder Is Over The Top

January 22, 2023 by 6 Comments

Like most of us, [Arnov] used a spare coffee mug to hold pens on his desk. But there has to be a better way, right? Surely if you build a better mouse trap… or, in this case, a pen holder. He’d be the first to admit that he might have gotten a little carried away, but the result is an attractive pen holder made from PCB material, one of which is actually an active circuit board.

The pen holder has some power management, as there’s a rechargeable battery that allows it to charge devices such as a smartphone or an embedded board. The power is also available for LEDs in the pen holder. The PCBs are bound together with 3D printed brackets.

The non-functioning PCBs still have patterns etched to make them more interesting looking. This is one of those things that isn’t technically a big deal, but we really liked the look of it, which was quite professional. We’ve seen PCBs used as enclosures before, but making the pattern and improving light transmission by removing the solder mask were nice touches.

If you don’t like the idea of making enclosures from PCB material, don’t forget they can form other components, as well. Clever arrangements can build resistors, capacitors, and inductors not to mention exotic transmission line elements.

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Off-Grid Van Build Uses 3D Scanning For Smarter Planning

January 22, 2023 by 44 Comments

Folks who refurbish and rebuild vans into off-grid campers (especially with the ability to work in them remotely) put a fantastic amount of planning and work into their projects. [Rob] meticulously documented his finished van conversion and while he does a ton of clever work, we especially liked how he shows modern tools like photogrammetry can improve the process.

Photogrammetry helped turn a bunch of photos from different angles into a textured 3D model with accurate dimensions.

[Rob] used a camera and photogrammetry software to 3D scan the van inside and out. The resulting model means that CAD tools can better assist with the layout and design phase. This is an immense help, because as [Rob] points out, an empty van is anything but a hollow box on wheels. Every surface is curved, none of the sides are identical, and there frankly isn’t a right angle to be found anywhere. When every little scrap of space counts, it’s important to have an accurate reference.

Of course, mapping the work are was just the beginning. It took six months, but he turned a Volkswagen Crafter cargo van into a slick off-grid camper capable of remote work. The full series of videos is on his site, but you can also watch the video highlights, embedded below.

The photogrammetry was done with Meshroom, and if you’d like to know more, we’ve previously explained different 3D scanning methods and how they can help with design work like this.

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A four-fingered partial hand prosthesis in fuschia with black fingerpads is attached to a man's left hand (palm and thumb are original). He holds the left hand + prosthetic with his right hand and an aluminum hand prosthetic sits on the table to the left of his hands.

Designing A Simpler Prosthetic Finger

January 22, 2023 by 5 Comments

Prosthetic limb design is an area where desktop manufacturing has made huge strides, but there’s always room for improvement. For example, take a look at [Ian Davis] and his attempts to design a simpler prosthetic finger.

[Davis] favors his aluminum partial hand prosthetic for its strength, but because it was scratch built for his particular situation, it isn’t easy to recreate for someone else. To this end, he has started working on a simpler design that might be applicable in the future for people who want to build their own prosthetics. With less than ten major components per finger including the replaceable TPU fingerpads, this is a major step toward that end.

According to [Davis], one of the more exciting parts of the build is that while this hand has a more limited feature set, he was able to get it closer to the size of his natural hand. Because of the durability problems he’s experienced for day-to-day use of plastic prosthetics, he is having the next iteration 3D printed in stainless steel for further testing.

If you want to see some more interesting prosthetic designs, checkout the Kid Who Designed His Own Prosthetic Arm or this Skull Lamp Prosthetic Eye.

DIY capacitor leakage tester nestled among neighbours all mounted underneath a shelf

DIY Capacitor Leakage Tester With A Professional Finish

January 22, 2023 by 7 Comments

[Manuel Caldeira] has built a nice electronics work area that would be the envy of many, complete with an under-shelf rail of custom-built instruments that are specific to the needs of areas of electronics that [Manuel] is involved with. The highlighted project here is a capacitor leakage tester, which is very handy for sorting through piles of old parts looking for anything still within spec, or just verifying a part on a board is the culprit you suspect it is.

The thing is, certain types of capacitors have a limited life both in operation and in storage. Usually, we’re talking about electrolytics here, where the electrolyte solution can leak out or dry out, but also the passive oxide layer on the anode plate can deteriorate if the device is left unpowered for long periods — the oxide disintegrates, and the capacitor will start to leak current. Eventually, the breakdown can be bad enough for the capacitor to conduct so well that it overheats and the result can be a surprisingly violent experience. So, if you deal with capacitors a lot, especially electrolytics, then a leakage tester is a very good instrument to own.

We like [Manuel]’s construction method here, with custom PCBs nestled inside a simple bent aluminium enclosure. No need for a top or sides, as these, are intended to bolt underneath a shelf, and butt up against their neighbor. The front panel graphics are done in a simple but very effective manner, using printable sticker sheets, with a clear adhesive over-sheet. They certainly have a professional finish, and this is definitely a construction method worth considering.

For those a little unfamiliar with this important component, why not leap into some theory with this handy dive into the simple parallel plate capacitor? Next, may we suggest a little overview of the different capacitor types and how to best make use of them?

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Wii Turned Expansion Card For Broadcast Monitor

January 22, 2023 by 9 Comments

For the proper retro gaming aesthetic, plenty of gamers look to old CRT displays. Older games can look better on these displays because the original programmers took their visual characteristics into account. Finding a CRT from the 90s or early 2000s is one option, but an even better option is a broadcast video monitor (BVM) which were extremely high quality CRTs with some other features, like the ability to install a Wii straight to an expansion port on the monitor itself (Nitter).

These monitors were, as their name implies, made for broadcast TV productions. As such, they don’t have the typical video connections that might be found on a consumer unit. Instead, they used modular cards to interface with the monitor. Thanks to an open design for cards made for Sony monitors, [ShankMods] was able to make one for the Wii by “trimming” away the unnecessary parts of the console’s PCB and mapping its video and audio outputs to the slot connector.

While the Wii might not be everyone’s idea of retro, it was still a console that came out when plenty of people still had CRTs as their primary home television. It isn’t as necessary to have a CRT for a Wii as some of the older consoles, but it was very easily adaptable to this single-board design. If you don’t have a CRT and still want the CRT feel, there are ways of retrofitting a more modern display to get this effect, though.

Thanks to [Jonas] for the tip!

An Unexpected Amiga Network Interface

January 21, 2023 by 31 Comments

The retrocomputer enthusiast has increasingly to grapple with not only runaway computer prices but the astronomical cost of vintage peripherals. A welcome solution in some cases comes from the Raspberry Pi, which has proved itself fast enough to emulate those add-ons for a lot less outlay. A good one comes from [Niklas Ekström], who’s made a Pi-based network adapter for the Commodore Amiga 1200. Better still it doesn’t hog the main expansion port or the PCMCIA slot, instead it sits on the 1200’s rarely-used real-time-clock port. Software wise it uses an updated version of his earlier project for the Amiga 500. It provides access to the Pi command prompt, as well as a SANA driver and a mounted filesystem.

While many of us view the Amiga from 2023 as a retro gaming platform, for those of us who used it at the time it was a desktop productivity machine on a more affordable budget than the Macintosh. At the time the thought of having a UNIX-like operating system running on a super-powerful co-processor in your Amiga would have been beyond our wildest dreams, but whether it provides enough now to make a 1992 machine compete on the desktop is debatable. Who wants to run Firefox from the Pi in an X server on the Amiga?

An illustration of a key sitting on an ID card. The key is light grey and the ID card is a darker grey gradient. The ID card says ID-1 Card 85.60 by 53.98 mm

All Your Keys Are Belong To KeyDecoder

January 21, 2023 by 56 Comments

Physical security is often considered simpler than digital security since safes are heavy and physical keys take more effort to duplicate than those of the digital persuasion. [Maxime Beasse and Quentin Clement] have developed a smartphone app that can duplicate a key from a photo making key copying much easier.

KeyDecoder is an open source Android app that can generate all the necessary bitting info to duplicate a key from just an image. Luckily for the paranoid among us, the image must be taken with the key laying flat without a keyring on an ISO/CEI 7810 ID-1 ID or credit card. A passerby can’t just snap a photo of your keys across the room and go liberate your home furnishings, but it still would be wise to keep a closer eye on your keys now that this particular cat hack is out of the bag.

The project’s GitHub page is awash in warnings that this tool is designed solely for “pentesters and security enthusiasts” to warn their friends and clients about the dangers of leaving their keys exposed. After learning about this tool, we wouldn’t be surprised if some in the audience start rethinking how they carry and store their physical keys from now on.

If you want to see some more hacks to duplicate keys, checkout Copying High Security Keys With OpenSCAD And Light and Methods Of Copying High Security Keys.