So Where’s My Low Voltage DC Wall Socket?

What are the evocative sounds and smells of your childhood? The sensations that you didn’t notice at the time but which take you back immediately? For me one of them is the slight smell of phenolic resin from an older piece of consumer electronics that has warmed up; it immediately has me sitting cross-legged on our living room carpet, circa 1975.

"Get ready for a life that smells of hot plastic, son!" John Atherton [CC BY-SA 2.0], via Wikimedia Commons.
“Get ready for a life that smells of hot plastic, son!” John Atherton [CC BY-SA 2.0], via Wikimedia Commons.
That phenolic smell has gone from our modern electronics, not only because modern enclosures are made from ABS and other more modern plastics, but because the electronics they contain no longer get so hot. Our LCD TV for instance nowadays uses only 50 watts, while its 1970s CRT predecessor would have used several hundred. Before the 1970s you would not find many household appliances that used less than 100 watts, but if you take stock of modern electrical appliances, few use more than that. Outside the white goods in your kitchen and any electric heaters or hair dryers you may own, your appliances today are low-powered. Even your lighting is rapidly being taken over by LEDs, which are at their heart low-voltage devices.

There are many small technological advancements that have contributed to this change over the decades. Switch-mode power supplies, LCD displays, large-scale integration, class D audio and of course the demise of the thermionic tube, to name but a few. The result is often that the appliance itself runs from a low voltage. Where once you would have had a pile of mains plugs competing for your sockets, now you will have an equivalent pile of wall-wart power supplies. Even those appliances with a mains cord will probably still contain a switch-mode power supply inside.

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80-PIC32 Cluster Does Fractals

One way to get around limitations in computing resources is to throw more computers at the problem. That’s why even cheap consumer-grade computers and phones have multiple cores in them. In supercomputing, it is common to have lots of processors with sophisticated sharing mechanisms.

[Henk Verbeek] decided to take 80 inexpensive PIC32 chips and build his own cluster programmed in — of all things — BASIC. The devices talk to each other via I2C. His example application plots fractals on another PIC32-based computer that has a VGA output. You can see a video of the device in action, below.

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Portable Apple II On An AVR

The Apple II was one of the first home computers. Designed by Steve “Woz” Wozniak, it used the MOS technologies 6502 processor, an 8-bit processor running at about 1 MHz. [Maxstaunch] wrote his bachelor thesis about emulating the 6502 in software on an AVR1284 and came up with a handheld prototype Apple II with screen and keyboard.

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Prototype on veroboard

Originally, [maxstrauch] wanted to build an NES, which uses the same 6502 processor, but he calculated the NES’s Picture Processing Unit would be too complicated for the AVR, so he started on emulating the Apple II instead. It’s not quite there – it can only reference 12K of memory instead of the 64K on the original, so hi-res graphic mode, and therefore, many games, won’t work, but lo-res mode works as well as BASIC (both Integer BASIC and Applesoft BASIC.)

[Maxstrauch] details the 6502 in his thesis and, in a separate document, he gives an overview of the project. A third document has the schematic he used to build his emulator. His thesis goes into great detail about the 6502 and how he maps it to the AVR microcontroller. The build itself is pretty impressive, too. Done on veroboard, the build has a display, keyboard and a small speaker as well as a micro SD card for reading and storing data. For more 6502 projects, check out the Dis-Integrated 6502 and also, this guide to building a homebrew 6502.

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How Has Amazon Managed To Make Hackers Love Alexa?

Our hackspace has acquired an Amazon Dot, courtesy of a member. It mostly seems to be used as a source of background music, but it has also spawned a seemingly never-ending new entertainment in which the hackspace denizens ceaselessly bait their new electronic companion with ever more complex and esoteric requests. From endless rephrasing and careful enunciation of obscure early reggae artists to try to settle a musical argument to hilarious mis-hearing on the part of our silicon friend, the fun never stops. “Alexa, **** off!” it seems results in “I’m sorry, I can’t find a device of that name on this network”.

amazon-dot-always-listeningThat is just the experience of one hackspace, but it evidently does not end there. Every other day it seems that new projects using Alexa pass through the Hackaday timeline, so it looks as though Amazon’s online personal assistant has been something of a hit within our community.

Fair enough, you might say, we’re always early adopters of any new technology. But it’s a development over which I wonder; am I alone in finding it surprising? It’s worth taking a moment to look at the subject.

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Raspberry Pi Zero smart projector

Smart Projector With Built-in Raspberry Pi Zero

You’ve heard of smartphones but have you heard of smart projectors? They’ve actually been around for a few years and are sort of like a TV set top box and projector combined, leaving no need for a TV. Features can include things like streaming Netflix, browsing in Chrome, and Skyping. However, they can cost from a few hundred to over a thousand dollars.

[Novaspirit]  instead made his own cheap smart projector. He first got a $70 portable projector (800×480 native resolution, decent for that price) and opened it up. He soldered an old USB hub that he already had to a Raspberry Pi Zero so that he could plug in a WiFi dongle and a dongle for a Bluetooth keyboard. That all went into the projector.

Examining the projector’s circuit board he found locations to which he could wire the Raspberry Pi Zero for power even when the projector was off. He lastly made the Raspberry Pi dual-bootable into either OSMC or RetroPie. OSMC is a Linux install that boots directly into a media player and RetroPie is a similar install that turns your Raspberry Pi into a gaming machine. You can see a timelapse of the making of it and a demonstration in the video after the break.

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Cheap Chainsaw Teardown Reveals Buried Treasures

People seem to have a love-hate relationship with Harbor Freight, and it mostly seems that they love to hate the purveyor of discount tools. This is not without cause — any number of HF tools have fallen apart in our hands. But there are some gems to be found amid the dregs and dross of your local branch of the 700-store US chain, as long as you match the tool to your needs and manage your expectations.

Now, we’d normally shy away from any electric chainsaw, especially a cordless saw, and doubly so a Harbor Freight special. But as [Professor Charles] demonstrates with his detailed and humorous teardown, the Lynxx 40-volt cordless 14″ chainsaw might be worth picking up just for harvesting parts. First there’s the battery pack, which is chock full of 18650 lithium cells. [Professor Charles] leads us on a detailed tour of the design compromises of the battery and charger and is none too impressed with either, but he clearly understands what it means to build to a price point. While [Charles] found the stock motor controller somewhat anemic, the real buried treasure in the tool is a huge brushless motor, powerful enough to “throw an 8-inch Vise Grip at you” during a (not so) locked rotor test.

The whole teardown is enlightening as to the engineering decisions that go into mass-market tools, so even if you can’t think of something to do with this motor, the article is worth a read. At $169 for the Lynxx (before the 20% coupon in your Sunday paper every week) it’s a little pricey to buy just to harvest parts, but it wouldn’t be the first HF tool to suffer that fate. We’ll bet these things will start showing up broken on the secondary market for a song, and if the [Professor]’s assessments are right, it likely won’t be the motors that fail.

Harrowing Story Of Installing Libreboot On ThinkPad

As an Apple user, I’ve become somewhat disillusioned over the past few years. Maybe it’s the spirit of Steve Jobs slowly vanishing from the company, or that Apple seems to care more about keeping up with expensive trends lately rather than setting them, or the nagging notion Apple doesn’t have my best interests as a user in mind.

Whatever it is, I was passively on the hunt for a new laptop with the pipe dream that one day I could junk my Apple for something even better. One that could run a *nix operating system of some sort, be made with quality hardware, and not concern me over privacy issues. I didn’t think that those qualities existed in a laptop at all, and that my 2012 MacBook Pro was the “lesser of evils” that I might as well keep using. But then, we published a ThinkPad think piece that had two words in it that led me on a weeks-long journey to the brand-new, eight-year-old laptop I’m currently working from. Those two words: “install libreboot”.

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