Author: Jenny List

2748 Articles

How To Cast Silicone Bike Bits

April 26, 2024 by 18 Comments

It’s a sad fact of owning older machinery, that no matter how much care is lavished upon your pride and joy, the inexorable march of time takes its toll upon some of the parts. [Jason Scatena] knows this only too well, he’s got a 1976 Honda CJ360 twin, and the rubber bushes that secure its side panels are perished. New ones are hard to come by at a sensible price, so he set about casting his own in silicone.

Naturally this story is of particular interest to owners of old motorcycles, but the techniques should be worth a read to anyone, as we see how he refined his 3D printed mold design and then how he used mica powder to give the clear silicone its black colour. The final buses certainly look the part especially when fitted to the bike frame, and we hope they’ll keep those Honda side panels in place for decades to come. Where this is being written there’s a CB400F in storage, for which we’ll have to remember this project when it’s time to reactivate it.

If fettling old bikes is your thing then we hope you’re in good company here, however we’re unsure that many of you will have restored the parts bin for an entire marque.

Reverse Engineering A Fancy Disposable Vape

April 25, 2024 by 21 Comments

Many readers will be aware of the trend for disposable vapes, and how harvesting them for lithium-ion batteries has become a popular pastime in our community. We’re all used to the slim ones about the size of a marker pen, but it’s a surprise to find that they also come in larger sizes equipped with colour LCD screens. [Jason Gin] received one of this type of vape, and set about reverse engineering it.

What he found inside alongside the lithium-ion cell (we love his use of the term ” street lithium” by the way) was an ARM Cortex M0 microcontroller, 1 MB of flash, and that 80×160 display. Some investigation revealed this last part to have an ST7735S controller with an SPI interface. He turned his attention to the flash, which was filled with the bitmaps for the display. Seeing an opportunity there, this lead to the creation of a Windows 95 theme for the device.

Finally, the microcontroller turned out to be accessible with programming tools, with an unprotected firmware. The reverse engineering effort is ongoing, but we hope the result is a small dev board that will at least save some of the from being e-waste. If you’re curious, all the tools used are in a GitHub repository.

Meanwhile, we’ve looked at street lithium harvesting before.

Thanks [DeadFishOnTheLanding] for the tip!

The First European Pocket Calculator Came From Yugoslavia

April 24, 2024 by 8 Comments

At the start of the 1970s the pocket calculator was the last word in personal electronics, and consumers in Europe looked eagerly towards Japan or the USA for a glimpse of new products. Meanwhile the European manufacturers, perhaps Philips in the Netherlands, or Olivetti in Italy, would no doubt have been putting their best engineers on to the task of delivering the first domestic European models.

So who was first with a European-made calculator? Not the Dutch, the Italians, the Germans, or even the Brits, instead that honour went to the Yugoslavians. Digitron is a company located in Buje, in modern-day Croatia, and they pipped everyone else in Europe to the post back in 1971 with their DB800 model.

We read about the achievement through the above-linked exhibition, but perhaps the greatest surprise comes in finding relatively little technical information online about these machines. Other early calculators have been subjected to extensive teardowns, so we can see all manner of interesting period tech. This one however, other than references to using Japanese parts, has very little. Whose chip did it use, and were there any quirky design choices made? We hope that someone out there has one and is prepared to give the world a peek.

Meanwhile, we’ve looked at a few older calculators ourselves.

An Elbow Joint That Can

April 23, 2024 by 10 Comments

We’re not certain whether [Paul Gould]’s kid’s prosthetic elbow joint is intended for use by a real kid or is part of a robotics project — but it caught our eye for the way it packs the guts of a beefy-looking motorized joint into such a small space.

At its heart is a cycloidal gearbox, in which the three small shafts which drive the center gear are driven by a toothed belt. The motive power comes from a brushless motor, which is what gives the build that impressive small size. He’s posted a YouTube short showing its internals and it doing a small amount of weight lifting, so it evidently has some pulling power.

If you’re interested in working with this design, it can be downloaded for 3D printing from Thingiverse. We think it could find an application in plenty of other projects, and we’d be interested to see what people do with it. There’s certainly a comparison to be maid over robotic joints which use wires for actuation.

Continue reading “An Elbow Joint That Can” →

Your Smart TV Does 4K, Surround Sound, Denial-of-service…

April 23, 2024 by 46 Comments

Any reader who has bought a TV in recent years will know that it’s now almost impossible to buy one that’s just a TV. Instead they are all “smart” TVs, with an on-board computer running a custom OS with a pile of streaming apps installed. It fits an age in which linear broadcast TV is looking increasingly archaic, but it brings with it a host of new challenges.

Normally you’d expect us to launch into a story of privacy invasion from a TV manufacturer at this point, but instead we’ve got [Priscilla]’s experience, in which her HiSense Android TV executed a denial of service on the computers on her network.

The root of the problem appears to be the TV running continuous network discovery attempts using random UUIDs, which when happening every few minutes for a year or more, overloads the key caches on other networked machines. The PC which brought the problem to light was a Windows machine, which leaves us sincerely hoping that our Linux boxen might be immune.

It’s fair to place this story more under the heading of bugs than of malicious intent, but even so it’s something that should never have made it to production. The linked story advises nobody to buy a HiSense TV, but to that we’d have to doubt that other manufactures wouldn’t be similarly affected.

Header: William Hook, CC-BY-SA 2.0.

Thanks [Concretedog] for the tip.

Keeping Alive The Future Of Cars, 1980s Style

April 21, 2024 by 18 Comments

Here at Hackaday we’re a varied bunch of writers, some of whom have careers away from this organ, and others whose work also appears on the pages of other publications in different fields. One such is our colleague [Lewin Day], and he’s written a cracking piece for The Autopian about the effort to keep an obscure piece of American automotive electronic history alive. We think of big-screen control panels in cars as a new phenomenon, but General Motors was fitting tiny Sony Trinitron CRTs to some models back in the late 1980s. If you own one of these cars the chances are the CRT is inoperable if you’ve not encountered [Jon Morlan] and his work repairing and restoring them.

Lewin’s piece goes into enough technical detail that we won’t simply rehash it here, but it’s interesting to contrast the approach of painstaking repair with that of replacement or emulation. It would be a relatively straightforward project to replace the CRT with a modern LCD displaying the same video, and even to use a modern single board computer to emulate much of a dead system. But we understand completely that to many motor enthusiasts that’s not the point, indeed it’s the very fact it has a frickin’ CRT in the dash that makes the car.We’ll probably never drive a 1989 Oldsmobile Toronado. But we sure want to if it’s got that particular version of the future fitted.

Lewin’s automotive writing is worth watching out for. He once brought us to a motorcycle chariot.

An Open-Source Gaming Mouse

April 21, 2024 by 12 Comments

It’s a shame, that peripherals sold as of higher performance for gaming so often deliver little but aggressive styling. [Wareya] became frustrated with the fragile switches on his choice of gaming mouse, so decided to design his own. In the video that he’s placed below the break, he takes us through all the many choices and pitfalls inherent to these devices

After quite a few iterations he arrived upon a design featuring an RP2040 and an optical sensor easily found in relatively inexpensive mice. The whole design is open source and can be found in a GitHub repository, but for us perhaps the most interesting part of the explanation lies in the use of a three-contact switch, and how the third contact is used to aid in debouncing. In an application in which latency is of paramount importance this is a key design feature of a gaming mouse.

Perhaps it’s a mark of how good computer mice are in general that we see so relatively few projects building them from scratch rather than modifying exiting ones, but despite that a few have made it to these pages. Continue reading “An Open-Source Gaming Mouse” →