Happy Meal Hack Produces a Google Cardboard Test

Ever since Google Cardboard came out, [Julian Jackson] had been meaning to give it a shot. Affordable virtual reality? Who wouldn’t! But, he never got around to it — until one day he was sitting in McDonald’s with his son, explaining to him how the latest Happy Meal toy worked — it was a pair of penguin binoculars.

Fast forward past Thanksgiving and Black Friday and [Julian’s] son had completely forgotten about the McDonald’s toy in all the excitement, so [Julian] asked if he could have it. His son was mildly confused, but curious also, so he let his dad take his toy.

After attempting to dismantle it with a screw driver to get at the lenses, [Julian] carefully calculated the best place to simply break it without damaging them. With the precision of a heart surgeon he swung back his trusty hammer…  Continue reading “Happy Meal Hack Produces a Google Cardboard Test”

Philly Fixers Guild Will Teach You How to Fish

One crisp Saturday afternoon a couple of weeks ago, the Philly Fixers Guild held its second Repair Fair. Not second annual, mind you; the first fair was held in September. People came from miles around, hauling with them basement and attic treasures that needed, well, fixing. [Fran] is one of the Guild’s volunteer fixers, and she shot some video of the event which is waiting for you after the break.

The Philly Fixers Guild aims to promote sustainability in the surrounding community by teaching interested parties to repair their possessions that might otherwise end up in a landfill. The fairs are not meant to be a drop-off repair site—attendees are expected to stay and learn about what’s wrong with their item and how it can or can’t be fixed.

The Guild is open to volunteers who are interested in teaching people how to fish, as it were. Expertise is not limited to electronics repair; guild members are just as interested in teaching people how to sew a replacement button on their winter coat or building that thing they bought at IKEA.

Nowhere near Pennsylvania? Several groups like the Philly Fixers Guild have already been established in a few larger US cities. If you’re not near any of those either (and we can sympathize), you could do worse than to start your own. If you’re part of a ‘space, creating such a guild would be a good way to spread the word about it and the gospel of DIY.

In the video, [Fran] discusses an Atari 2600’s control problem with its owner. She re-seats the 6532 RIOT chip and explains that this may or may not have solved the problem. If not, [Fran] is confident that new old stock chips are available out there on the hinterwebs. There might still be some landfill carts on ebay if the owner gets it up and running. [Fran] also fixes the controls on a Peavey amp and gets some Pink Floyd to issue forth from a previously non-functioning Zenith portable AM/FM radio that’s old enough to have a snap cover.

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Geopolymer Concrete, Perfecting Roman Technology Today

For all the things Romans got wrong (lead pipes anyone?) did you know we’re still using a less advanced concrete than they did? Consider some of the massive structures in Rome that have passed the test of time, lasting for more than 2000 years. The typical concrete that we use in construction starts to degrade after only 50 years.

Researchers at Berkeley think they’ve finally figured it out with thanks to a sample that was removed from the Pozzuoli Bay near Naples, Italy. This could vastly improve the durability of modern concrete, and even reduce the carbon footprint from making it. The downside is a longer curing time, and resource allocation — it wouldn’t be possible to completely replace modern cement due to the limited supply of fly ash (an industrial waste product produced by burning coal). Their research can be found in a few articles, however they are both behind pay walls.

Lucky for us, and the open source community at large, someone from MIT has also been working on perfecting the formula — and he’s shared his results thus far.

So, who wants to give it a shot? Any material scientists in our midst?

Pico-Kubik Quadruped Fits in the Palm of your Hand

Most of the legged robots we see here are of the hexapod variety, and with good reason. Hexapods are very stable and can easily move even if one or more of the legs has been disabled. [Radomir] has taken this a step farther and has become somewhat of an expert on the more technically difficult quadruped robot, building smaller and smaller ones each time. He has been hard at work on his latest four-legged creation called the Pico-Kubik, and this one will fit in the palm of your hand.

The Pico-Kubik runs Micropython on a VoCore board, which allows for it to have a small software footprint to complement its small hardware footprint. It accomplishes the latter primarily through the use of HK-282A Ultra-Micro Servos, an Arduino Pro Mini, and a tiny lithium ion battery. It’s still a work in progress, but the robot can already crawl across the tabletop.

This isn’t [Radomir]’s first time at the tiny quadruped rodeo, either. He has already built the Nano-Kubik and the µKubik, all of which followed the first (aptly-named) Kubik quadruped. Based on the use of SI prefixes, we can only assume the next one will be the hella-Kubik!

Scope Noob: Bridge Rectifier

Welcome back to this week’s installment of Scope Noob where I’m sharing my experiences learning to use my first oscilloscope. Last week I started out measuring mains frequency using an AC-AC wall wart adapter. Homework, for those following along, was to build a bridge rectifier and probe the signals from it. Let’s take a look.

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Fixing An NES For Good

Sometime in the late 80s, the vast collective consciousness of 8-year-olds discovered a Nintendo Entertainment System could be fixed merely by blowing on the cartridge connector. No one knows how this was independently discovered, no one knows the original discoverer, but one fact remains true: dirty pins probably weren’t the problem.

The problem with a NES that just won’t read a cartridge is the ZIF socket inside the console. Pins get bent, and that spring-loaded, VCR-like front loader assembly is the main point of failure of these consoles, even 30 years later. You can get replacement ZIF sockets for a few bucks, and replace the old one using only a screwdriver, but this only delays the inevitable. That ZIF socket will fail again a few years down the line. Finally, there is a solution.

The Blinking Light Win, as this project is called, replaces the ZIF connector with two card-edge slots. One slot connects to the NES main board, the other to the cartridge connector. There’s a plastic adapter that replaces the spring-loaded push down mechanism created for the original ZIF connector, and installation is exactly as easy as installing a reproduction NES ZIF connector.

If you’re wondering why consoles like the SNES, Genesis, and even the top-loader NES never had problems that required blowing into the cartridge connector, it’s because the mere insertion of the cartridge into the slot performed a scrubbing action against the pins. Since the ZIF socket in the O.G. NES didn’t have this, it was prone to failure. Replacing the ZIF with a true card-edge slot does away with all the problems of dirty contacts, and now turns the NES into something that’s at least as reliable as other cartridge-based consoles.

Popular Electronics Magazine Archive Online

They began publishing Popular Electronics magazine in 1954, and it soon became one of the best-selling DIY electronics magazines. And now you can relive those bygone days of yore by browsing through this archive of PDFs of all back issues from 1954 to 1982.

Reading back through the magazine’s history gives you a good feel for the technological state of the art, at least as far as the DIYer is concerned. In the 1950s and 1960s (and onwards) radio is a big deal. By the 1970s, hi-fi equipment is hot and you get an inkling for the dawn of the digital computer age. Indeed, the archive ends in 1982 when the magazine changed its name to Computers and Electronics magazine.

It’s fun to see how much has changed, but there’s a bunch of useful material in there as well. In particular, each issue has a couple ultra-low-parts-count circuit designs that could certainly find a place in a modern project. For example, a “Touch-Controlled Solid State Switch” in July 1982 (PDF), using a hex inverter chip (CD4049) and a small handful of passive components.

But it’s the historical content that we find most interesting. For instance there is a nice article on the state of the art in computer memory (“The Electronic Mind — How it Remembers”) in August 1956 (PDF).

Have a good time digging through the archives, and if you find something you really like, let us know in the comments.