Got an old radio from the '20s, and want to bring it back to life? Well, the quickest way is probably be to remove all those dusty components and use the cabinet to hide a new stereo. That's not what radio hacker Greg Charvat had in mind for his, though. Instead, he restored the original radio circuitry, and even hooked it up to his iPod.

Along the way, he ran into all sorts of neat discoveries, and many potential pitfalls. It turns out that electronics have changed quite a bit in the past 80 years, and even the most basic components such as resistors and capacitors can be unrecognizable. Another issue is that the cloth and rubber used for insulation on the wiring will have dried out, making it necessary to handle everything extremely carefully. One nice thing about equipment of this vintage, however, is that it was usually designed to be repaired, so chances are good that a schematic is available.

To give you an idea of the issues one should expect to encounter when attempting this, here is the overview he gives in a presentation about the project:

• Do not power up your radio!
• yes, it does not work
• more harm than good
• Find service manual
• Replace all electrolytic and paper capacitors
• Replace anything that looks damaged (burned or exploded)
• Try radio (wear safety glasses)
• Signal trace through circuit, replacing resistors where needed
• Radio will work

As usual for high-voltage projects, and especially for high-voltage projects involving unknown vintage equipment, don't attempt this unless you have the proper training, because the electronics inside are most certainly deadly. Don't give up though, just make sure you learn enough to know what you are doing!

Johanna Bunn, of the Boston Museum of Science, introduced the Engineering the Future curriculum, with interactive demonstrations of hands-on projects introducing students to structures, fluids, and electricity.

The forum on the Massachusetts state science and technology curriculum frameworks introduced a series of strand maps that show how the concepts and possible activities in the various STEM subjects interrelate. Their hope is that existing and new courses could be designed so that they step students through learning ideas within courses and how the courses could build upon each other. Right now, the maps are static PDFs, but their goal is to have them be more interactive in the way they connect projects and concepts.

Martha Cyr, Director of K-12 Outreach at the Worcester Polytechnic Institute, showed the TEACHEngineering site, which has resources for K-12 teachers. The site's search engine allows teachers to find curriculum and projects that map to many states' frameworks, and loads of scientific and engineering concepts. The curriculum tools on the site have a consistent look and feel and have been tested by STEM teachers.

Nate Ball of Design Squad told of his experiences in backyard, garage, and kitchen making. Though his school in Oregon lacked a hands-on technology and engineering program, his childhood was filled with adventures of the making sort. His rigorous personal projects and academic record led him to MIT, where he discovered what engineers do. When WGBH uncovered a need for youth to understand more about the realities and techniques of engineering, he was in a group of students who helped to develop possible projects for the show before he tested for and ultimately filled the role of host. The show encourages creativity, teamwork, and real world problem solving. The third season of Design Squad has just begun airing, and the site has lots of curriculum resources, and full episodes of the show.

If you are involved in an organization helping to prepare teachers and their students for a lifetime of making, pass along some links in the comments.

To "shoot," an anvil, for the record, is to blast it several hundred feet into the air using a charge of black powder. This delightful man, Gay Wilkinson, is apparently the world's champion anvil-shooter. The fireworks start at 1:30. [via Boing Boing]

Alan Parekh of Hacked Gadgets made this really nice looking gear clock using a PIC microcontroller, a scavenged stepper motor, and a bunch of wooden gears that he cut out on a CNC router. The concept is pretty straightforward, however I really like the clear design, where each part is a functional piece of the clock mechanism. You'll never have to wonder what is inside this thing that makes it tick! [via Hacked Gadgets]

By deviantART user ~tallydragon. [via CRAFT]

Here's an excellent use for a giant LED billboard: a crazy augmented reality installation. The appropriately titled Hands From Above was made by artist Chris O'Shea. Want to create your own? You might run into trouble finding such a nice billboard to use, however the programming environments he used- openFrameworks and openCV - are both freely available. His source code doesn't seem to be available though, unfortunately. [via interactive architecture]

These days, homebrew CNC machines seem to be losing popularity to 3d printers. These are all well and good, however there are situations where you really need a part made of solid metal or wood, and for those there is no substitute to a good ol' CNC machine. So, it's nice to see that Jonny D is making progress on his homebrew CNC router. After getting a sweet deal on a suitable mechanical frame and stepper motors, he has managed to get his version up and running, and has successfully used it to engrave wood and drill PCBs. He's still working on improving the system, however this early success should be a great motivator to get everything finished up. Excellent work!

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While we're on the topic of low-tech visualizers, here is another neat one. This Lightfader floor has a (presumably slow moving) fluid in it, that gets displaced when you step on it, and then slowly returns to it's original state. This produces a footprint path that slowly fades away, without any electronics. It is a few years old, however I just became aware of it.

It kind of reminds me of what happens to your footprints when you walk down a beach, and then the waves wash them away. I'm guessing it is made of a thin layer of very viscous, tinted liquid. Think that would work, or does it have to be something more complicated? Perhaps some sort of liquid crystal-based polarizer, to improve the contrast? [via transmaterial]

The folks at BERG developed this neat method for visualizing the sensitivity of an RFID reader. Rather than using an expensive set of test equipment to measure the magnetic field intensity, they just hooked their reader up so that it lit an LED every time their card was detected, and then captured it using a camera. This is pretty similar to the technique used to make the Roomba art. They were also able to show that (due to polarization) the orientation of the card with respect to the sensor changes how it responds. Fascinating!

I'm digging the rocks supporting this 'Agua Table' by designer Domingos Tótora. Though they look totally real, they are actually made of recycled paper and glue. His website is made of unlinkable flash, however Contemporist has a nice set of photos showing how they are made.

The table is pretty nice, but I think I would want to make a giant boulder and roll it towards my anthropologist friends. What would you make out of fake rock? [via curbly]

I'd like to reassure everyone that Stormdrane is not paying me under the table. But public denials cost an extra $50 and he won't pony up the dough. So you're just gonna have to wonder. Seriously, I think I can't stop clicking through his blog because I'm looking for a "practical" excuse to tie one of these awesome knots. So far, this is the best one I've found. I may actually have to cave in and buy some neon paracord.

In the Maker Shed:


MiniPOV kit

This instrument is known both as a "glass harmonica" and a "glass armonica," and I personally favor the latter spelling to distinguish it from the better-known free-reed mouth harp also called a "harmonica." The tone of a glass armonica is stunningly beautiful; a great 18th-century myth is that the purity of its sound will eventually drive a virtuoso to madness. Thomas Bloch's website has more info about his work and about the particular custom-built instrument shown here. [via Neatorama]

More:

• Crazy glass armonica

More paracord goodness from Stormdrane.

Brad has a good start on what looks to be an ambitious electrical engineering project. Inspired by the Apollo guidance computer, he is constructing his own CPU using TTL logic chips and wire wrap. He's taking a little liberty with the design, using EEPROM chips for opcode decoding instead of hardwiring it all, but I think that can be excused. If you want to follow along and get some tips for your project, he also has a wiki to document his progress.

This project is kind of mad, but the results could be pretty useful. Instructables user catwood guides you through the process of building a wood lathe from mostly discarded parts. Along the way you will need things like the motor from a washing machine and the frame from a bike. It might make sense to buy or construct a more sturdy piece of equipment if you plan to make wood turning a full time hobby, but for light duty projects I could definitely see this coming in hand.

Steve writes in with these build instructions for a classic bathtub playtoy, the tugboat. At first glance it seemed like a regular old wooden play boat, but there is something cooler here- it has a working steam engine!

I hadn't heard of pop-pop boats before, but apparently they used to be common toys. The pop-pop motor is a phase-change heat engine (fancy name for a device that converts heat into kinetic energy), and the popping sound is caused when the water turns into steam and causes the metal cavity to expand. Here is a video of someone else's build:

This looks like a pretty fun experiment- anyone make one of these before? Bonus points if it can be remote controlled.

What could be better than a tube amplifier? How about an entire surround sound system built using tubes! Radar hacker Greg Charvat built such a beast back in 2005, and he refers to it affectionately as Frankenstein. Besides being an excellent, high-powered stereo, word on the street is that it also functions as a very capable space heater.

This is a good example of a project that has become completely out of control. At some point in the past I decided to build an all-tube home theater system (except for the DSP stuff that decodes the various Dolby 5.1, and etc signals). The result of this effort is affectionately known as "Frankenstein." It consists of 5 class AB tube power amplifiers, tube pre-amps, and a Dolby 5.1/DTS digital signal processor, for a total of 27 vacuum tubes. Each power amplifier is capable of over 400 watts peak output. All of the equipment is mounted in a 7' tall WW2 vintage equipment rack.

Schematics and engineering notes are available on his website, if you are up to the challenge.

Gijs Gieskes hooked up a circuit bent camera to a VU meter to create the VU Cam. I really enjoy the neat look of his homebrew circuit board, and the repeatable-looking results it achieves on the camera. He also includes a schematic, in case you want to try making your own.

OK, OK, this is probably something you shouldn't try on yourself, a loved one, or even a close friend. Still, it's pretty flippin' amazing: a full-grown animal, permanently (apparently) cured of a genetic defect by a few injections. Can X-people be that far behind?

(That's a rhetorical question, BTW; those of you who know the real answer to that question is "yes," just chill and give me my moment.)

Here is the original abstract at Nature.

Tim Schwartz made clever use of an old indicator dial with his piece Paris, 2007. He is using an embedded system to monitor realtime search patterns, in order to determine which Paris is more popular. The meter is constantly updated to show the latest results. It sounds like a pretty fun project to attempt. Anyone know how to get a realtime feed of people's search patterns? [via core77]

To produce a naturally blue rose has been a dream of horticulturalists for almost as long as people have been breeding flowers. It turns out to be essentially impossible to do by traditional plant husbandry, and attempts have proved futile for so long that the blue rose itself has become a symbol of the impossible or the seemingly impossible, and only the rarest achievements call for their presentation as gifts. And until recently, even those rare occasions had to be served by artificially blue roses made by growing white roses in tinted water. Now, however, the Japanese company Suntory, in partnership with Australia's Florigene, have created a transgenic rose which incorporates a petunia gene to achieve a pale lilac color which is really only barely blue. It took them 13 years of work to do it, however, so I guess they've decided pale lilac is close enough.

Giancarlo Todone writes to tell us about his homebrew solution for converting an old keyboard to MIDI. The project is especially nice because he went beyond the standard on/off key detection, and added full velocity sensitivity for the keys. This means that the keyboard can detect how fast a key is pressed, allowing the keyboard to be played more expressively. Full schematics and source code are available on his website, however the writeup is in Italian.

These enterprising blacksmiths make their wares using bellows made from cement bags.

[via afrigadget]

So here's a random idea I had.

Most readers are probably familiar with Dave Gingery's series of books on building a set of homemade machine tools. The technique, basically, involves building an inexpensive homemade charcoal furnace and crucible for melting aluminum, then using traditional green-sand casting techniques to mold the various machine parts from wooden patterns. Much of the content of Gingery's books details the construction of these patterns.

As I have recently discovered, however, lost-foam casting is a much more accessible metal-casting technique than traditional green-sand. It requires no special flasks, no special sand, and no consideration of parting-line placement in designing patterns. Basically you make your pattern from styrofoam, bury it in sand, and pour hot aluminum into it. The foam vaporizes and diffuses into the sand, and you're left with a perfect aluminum duplicate. The only downside is that the pattern itself is destroyed, so if you screw up the casting or want more than one copy of a part you need a new pattern.

Here's what I'd like to see: Some enterprising soul with a CNC foam cutter could sell kits of the Gingery machine patterns ready-cut in XPS foam.

Then, if you wanted to build the Gingery tools, you wouldn't have to spend a lot of time learning the art of green-sand casting, or building the special tools required, or carpentering on the patterns themselves, most of which will only be used once anyway. You'd just buy a few ounces of pre-cut foam patterns in a kit, bury them in sand, and start pouring hot aluminum right away. Depending on sales volume, it might even be practical to make the foam patterns in conventional molds, the same way styrofoam packaging inserts are produced, at lower cost than CNC machining.

If you're interested, supportive, or (for your own unfathomable reasons) furious, feel free to sound off in the comments.

The fine folks at i3 Detroit built this giant, ridable bristlebot using a large motor, a pipe for an offset weight, and a bunch of push broom heads. They claim it is the worlds largest, which I tend to believe. Does anyone know of a larger one?

Also, I think the only proper way to respond to this is to make an even larger bristlebot and challenge them to a race. Detroit makers, you are on!

Photo credits: Matt Mets, Dug Song

All of that gear pr0n got me thinking about ridiculous mechanical gadgets, and what better than a mechanical linkage that can square a complex number? It's probably not as useful as the Peaucellier's Cell or Watt's Linkage, and I don't think it is possible to build, however I really like this somewhat extreme example of translating mathematical operations into mechanical computers. In the above calculator, the x-axis represents the real portion of the number, and the y-axis represents the imaginary portion. To make the 'calculator' work, you drag the green dot to the location of the number you want to square, and the location of the red dot tells you the answer.

You can try it out for yourself on Dori Elder's thesis site from 1999!