Month: April 2017

An Even Smaller BeagleBone

April 15, 2017 by 51 Comments

The BeagleBone famously fits in an Altoids tin. Even though we now have BeagleBone Blacks, Blues, and Greens, the form factor for this curiously strong Linux board has remained unchanged, and able to fit inside a project box available at every cash register on the planet. There is another Altoids tin, though. The Altoid mini tin is just over 60×40 mm, and much too small to fit a normal size BeagleBone. [Michael Welling] has designed a new BeagleBone to fit this miniature project box. He’s calling it the Pocketbone, and it’s as small as the mints are strong.

The Pocketbone is based on the Octavo Systems OSD355x family, better known as the ‘BeagleBone on a chip’. This chip features a TI AM355x ARM Cortex A8, up to 1GB of DDR3 RAM, 114 GPIOs, 6 UARTs, 2 SPIs, 2x Gigabit Ethernet, and USB. It’s housed in a relatively large BGA package that makes routing easy, and as a proof of concept [Jason Kridner] built a PocketBone in Eagle.

[Michael]’s version of the Pocketbone is based on the earlier proof of concept, with a few handy additions. There’s an IO expansion header, provisions for a battery input, a few fixes to the USB, and all the parts are on one side of the board facilitating easier assembly. This version of the Pocketbone was created using KiCad, which will endear the project to the Open Source community.

Measuring Capacitors At The Birth Of Rock And Roll

April 15, 2017 by 3 Comments

The late 1950s [Bill Haley], [Elvis Presley], and [Little Richard] were building a new kind of music. Meanwhile, electronic hobbyists were building their own gear from Heathkit. A lot of that gear shows you how far we’ve come in less than a century. [Jeff Tranter’s] YouTube channel is a great way to look at a lot of old Heathkit gear, including this really interesting “direct reading capacity meter.” You can see the video, below.

Measuring capacitance these days is easy. Many digital multimeters have that function. However, those didn’t exist in the 1950s–at least, not in the way we know them. The CM-1 weighed 5 pounds, had several tubes, and cost what would equate to $250 in today’s prices. Unlike other instruments of the day, though, the capacitance was read directly off a large analog meter (hence, the name). You didn’t have to interpret readings using a nomograph or move a knob to balance a bridge and read the knob’s position.

Continue reading “Measuring Capacitors At The Birth Of Rock And Roll” →

High Vacuum With Mercury And Glassware

April 15, 2017 by 32 Comments

If you want to build your own vacuum tubes, whether amplifying, Nixie or cathode-ray, you’re going to need a vacuum. It’s in the name, after all. For a few thousand bucks, you can probably pick up a used turbo-molecular pump. But how did they make high vacuums back in the day? How did Edison evacuate his light bulbs?

Strangely enough, you could do worse than turn to YouTube for the answer: [Cody] demonstrates building a Sprengel vacuum pump (video embedded below). As tipster [BrightBlueJim] wrote us, this project has everything: high vacuum, home-made torch glassware, and large quantities of toxic heavy metals. (Somehow [Jim] missed out on the high-voltage from the static electricity generated by sliding mercury down glass tubes for days on end.)

Continue reading “High Vacuum With Mercury And Glassware” →

PassivDom: Mobile Homes For Millenials

April 14, 2017 by 79 Comments

In many parts of the world, living in a trailer has gained a social stigma. We’re talking about a rectangular building placed on three wheels and towed to your preferred plot of land. It’s going to take a lot to break that social stigma, but this is a pretty sweet attempt.

PassivDom is an off-grid home. It sidesteps the electrical grid as well as water and sewer service. It’s marketed as utilizing revolutionary breakthrough in wall insulation which they claim makes it very easy to heat and cool. In addition to this self-sustaining angle, it taps into the tiny home movement with a footprint of just 36 m2 (4 m by 9 m; about 118 390 ft2 or 13′ by 30′).

For this to make sense you really need to get the “Autonomous” model, the only one that is designed for “off-grid” living and comes with solar panels and battery storage plus water storage and purification. That’ll set you back 59,900 € (about $63,461 USD) but hey, it does come with “high quality minimalistic furniture” which the best way we can think of to serve Ikea nesting instinct without saying the brand name. Yep, this ticks all the “marketing to millennials” boxes. We’re kind of surprised it’s not doing crowdfunding.

So where’s the hack? Obviously this is a hard sell at 1,664 €/m2 ($538 $163/ft2). A project of this size and scope is well within the purview of a single, motivated hacker, and arguably a weekend project for a well-skilled team from a hackerspace. Tiny Houses started as a build-it yourself so that’s already solved. We’ve seen what it takes for hackers to add solar to their RVs, and experiments in home-built power walls. Water storage and purification is already solved and quite affordable at the home store.

Has anyone built their own off-grid tiny house? If so, let us know what went into it. If not, what are you waiting for?

Build Your Own PC — Really

April 14, 2017 by 37 Comments

There was a time when building your own computer meant a lot of soldering or wire wrapping. At some point, though, building a PC has come to mean buying a motherboard, a power supply, and just plugging a few wires together. There’s nothing wrong with that, but [Scott Baker] wanted to really build a PC. He put together an Xi 8088, a design from [Sergey] who has many interesting projects on his site. [Scott] did a great build log plus a video, which you can see below.

As the name implies, this isn’t a modern i7 powerhouse. It is a classic 8088 PC with a 16-bit backplane. On the plus side, almost everything is conventional through-hole parts, excepting an optional compact flash socket and part of the VGA card. [Scott] acquired the boards from the Retrobrew forum’s inventory of boards where forum users make PCBs available for projects like this.

Continue reading “Build Your Own PC — Really” →

KFC Winged Aircraft Actually Flies

April 14, 2017 by 41 Comments

[PeterSripol] has made an RC model airplane but instead of using normal wings he decided to try getting it to fly  using some KFC chicken buckets instead. Two KFC buckets in the place of wings were attached to a motor which spins the buckets up to speed. With a little help from the Magnus effect this creates lift.

Many different configurations were tried to get this contraption off the ground. They eventually settled on a dual prop setup, each spinning counter to each other for forward momentum. This helped to negate the gyroscopic effect of the spinning buckets producing the lift. After many failed build-then-fly attempts they finally got it in the air. It works, albeit not to well, but it did fly and was controllable. Perhaps with a few more adjustments and a bit of trial and error someone could build a really unique RC plane using this concept.

Continue reading “KFC Winged Aircraft Actually Flies” →

Dual SIM Hack For Single SIM Slot Phones.

April 14, 2017 by 67 Comments

[RoyTecTips] shows us an ingenious hack which turns a single-SIM-slot phone into a fully functioning dual-SIM phone. All that’s needed for this hack is a heat-gun, solvent, micro SD card, nano SIM and some glue. The trick is that the phone has a SIM reader on the backside of an SD-card slot. Through some detailed dissection and reconstruction work, you can piggy-back the SIM on the SD card and have them both work at the same time.

Making the SD/SIM Franken-card is no picnic. First you start by filing away the raised bottom edge of the micro SD card and file down the side until the writing is no longer visible. Next get a heat gun and blast your nano SIM card until the plastic melts away. Then mark where the SIM card’s brains go and glue it on. Turn the phone on then, hey presto, you now have a dual SIM phone while keeping your SD storage.

This hack is reported to work on many Samsung phones that end in “7” and some that end in “5”, along with some 8-series phones from Huawei and Oppo clones of the Samsungs. Since you’re only modifying the SIM card, it’s a fairly low-risk hack for a phone. Combining two cards into one is certainly a neat trick, almost as neat as shoe-horning a microcontroller into an SD card. We wonder how long it will be before we see commercial dual SIM/SD cards on the market.

[Update] I got a little confused on this one as we only have the single sim variants of these phones where I live. this hack is for dual sim phones that either accept 2 sim cards or 1 sim + 1 SD card. This hack solves this problem and allows 2 sims plus 1 SD card in these phones. Sorry for the confusion and thanks to all who pointed this out in the comments.

Continue reading “Dual SIM Hack For Single SIM Slot Phones.” →