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Laser-Induced Graphene Supercapacitors from Kapton Tape

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From the sound of reports in the press, graphene is the miracle material that will cure all the world’s ills. It’ll make batteries better, supercharge solar panels, and revolutionize medicine. While a lot of applications for the carbon monolayer are actually out in the market already, there’s still a long way to go before the stuff is in everything, partly because graphene can be very difficult to make. It doesn’t necessarily have to be so hard, though, as [Zachary Tong] shows us with his laser-induced graphene supercapacitors . His production method couldn’t be simpler, and chances are good you’ve got everything you need to replicate the method in your shop right now. All it takes is a 405-nm laser, a 3D-printer or CNC router, and a roll of Kapton tape. As [Zach] explains, the laser energy converts the polyimide film used as the base material of Kapton into a sort of graphene foam. This foam doesn’t have all the usual properties of monolayer graphene, but it has interesting propertie

Tensions High After Second Failed Cable At Arecibo

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Today we’re sad to report that one of the primary support cables at the Arecibo Observatory has snapped , nudging the troubled radio telescope closer to a potential disaster. The Observatory’s 300 meter reflector dish was already badly in need of repairs after spending 60 years exposed to the elements in Puerto Rico, but dwindling funds have made it difficult for engineers to keep up. Damage from 2017’s Hurricane Maria was still being repaired when a secondary support cable broke free and smashed through the dish back in August, leading to grave concerns over how much more abuse the structure can take before a catastrophic failure is inevitable. The situation is particularly dire because both of the failed cables were attached to the same tower. Each of the remaining cables is now supporting more weight than ever before, increasing the likelihood of another failure. Unless engineers can support the dish and ease the stress on these cables, the entire structure could be brought down by

Trying (And Failing) To Use GPUs with the Compute Module 4

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The Raspberry Pi platform grows more capable and powerful with each iteration. With that said, they’re still not the go-to for high powered computing, and their external interfaces are limited for reasons of cost and scope. Despite this, people like [Jeff Geerling] strive to push the platform to its limits on a regular basis. Unfortunately, [Jeff’s] recent experiments with GPUs hit a hard stop that he’s as yet unable to overcome. With the release of the new Compute Module 4, the Raspberry Pi ecosystem now has a device that has a PCI-Express 2.0 1x interface as stock. This lead to many questioning whether or not GPUs could be used with the hardware. [Jeff] was determined to find out, buying a pair of older ATI and NVIDIA GPUs to play with. Immediate results were underwhelming, with no output whatsoever after plugging the modules in. Of course, [Jeff] didn’t expect things to be plug and play, so dug into the kernel messages to find out where the problems lay. The first problem was the

Retrotechtacular: Shake Hands with Danger

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OK, you’re going to have to engage your safety squints and sit back to enjoy this one: a classic bit of safety propaganda from US heavy-equipment manufacturer Caterpillar from 1980 entitled “ Shake Hands with Danger.” Actually, you’ll probably need to engage your schlock filters for this 23-minute film too, as both the writing and the theme song are pretty hard to take. The film is one of those “Scared Straight” attempts to show just how horrifically wrong things can go both in the field and in the shop when working on anything made of stuff stronger than human flesh and bone. And in that regard, the film is highly effective — we found ourselves getting a bit queasy at a few points, with the poor dude who got his hand sucked into a bench grinder being both terrifying and relatable. [Three-Finger Joe] indeed. Now, you might take exception with the acting, but as you watch all these vignettes, keep in mind that these are all old-school stunts — that’s actually a gigantic D9 bulldozer t

Xbox Series S Teardown Shows a Glimpse at the Future

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Console launch season is upon us. A time for billion dollar corporations ingratiate themselves with “Johnny Consumer” by promising the future of entertainment is finally available to one-and-all. The focus of this new generation of consoles has been the battle for 4K supremacy between Xbox Series X and PlayStation 5. Interestingly, Microsoft also created another iteration of their Xbox Series for those satisfied with games in 1080p, and thanks to [Dimitris] we have been able to see the internals of the Xbox Series S (XSS) . The Xbox Series S features standard m.2 slot that could be used for future storage expansion. Microsoft choosing to produce an all-digital console has greatly effected the internal design of the XSS. With the lack of a disc-drive there is only a single cable (the fan cable) tying the components together. The heat sink covering the 197mm² AMD APU takes up nearly 60% of the motherboard surface area. Though the XSS may be diminutive by modern console standards, its

Help, I’m Buried Alive By Tablets!

It’s fair to say that many Hackaday readers will have a propensity for hoarding electronic or tech junk. Who hasn’t hung on to something because “It might be useful someday”? Spare a thought for [Mike Drew], who in his own words is “buried alive by tablets”. In this case the tablets are Intel-based ones that look as though they ran one of those cut-down Windows versions, and they appear to be rejects from a repair shop processing customer returns that he saved from the dumpster. They are missing their backs, and not all of their screens work, but they amount to a tidy pile of Stuff That’s Too Good To Throw Away. The exact spec is a 1.4 GHz quad-core Atom with 4 GB of RAM and 32 GB of Flash, and appear from the photos to have HDMI and USB 3 interfaces. Happily they run Linux Mint 20 so they have plenty of potential, but there is only so much that one person can do with them before running out of ideas. He tells us he’s made a Folding@Home cluster, but beyond that he’s open to suggesti

Illuminating the Inner Workings of a Venus Flytrap

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As a carnivorous plant, Venus flytraps have always been a fascinating subject of study. One of their many mysteries is how they differentiate an insect visit from less nutritious stimulants such as a windblown pebble. Now scientists are one step closer to deciphering the underlying mechanism, assisted by a new ability to visualize calcium changes in real time . Calcium has long been suspected to play an important part in a Venus flytrap’s close/no-close decision process, but scientists couldn’t verify their hypothesis before. Standard chemical tests for calcium would require cutting the plant apart, which would only result in a static snapshot. The software analogy would be killing the process for a memory dump but unable to debug the process at runtime. There were tantalizing hints of a biological calcium-based analog computer at work, but mother nature had no reason to evolve JTAG test points on it. Lacking in-circuit debug headers, scientists turned to the next best thing: add dia