Wireless IPod Charger Built From Scratch

May 10, 2012 by Mike Szczys 20 Comments

Despite the obvious use of a lot of wire, this project is actually a wireless charging system. [Jared] built it as a way to explore the concepts behind transferring power inductively. Alternating current on one of the white coils induces current on the other. This is then rectified, and regulated for use as a 5V charger. In this case it powers his iPod, but any USB device should work with the setup.

The transmitter uses the power supply from an old laptop as a source. Some filtering and a couple of MOSFETS are responsible for generating the AC current on the transmitting coil. The receiving coil feeds the bridge rectifier. In the writeup that voltage is fed to a 7805 regulator to provide a stable 5V output. However, in the video demo after the break [Jared] shows off the boost converter that he uses on his improved circuit. This way if the voltage drops due to poor alignment of the coils it will still be able to provide a steady output.

We’ve seen the same coil concept used to add wireless charging to cellphones too.

Continue reading “Wireless IPod Charger Built From Scratch” →

You Might Be A Geeky Dad If: Your Kids Practice Spelling In Morse Code

May 8, 2012 by Mike Szczys 11 Comments

Kids learn better if they’re engaged in the topic at hand. [Todd] found something that has his son just begging to practice his spelling words each night. He converts them all to Morse code and taps each out on the Morse code practice station they built together. To start off Todd connected the keyer to his Fluke 87 meter, using the continuity tester to sound a beep each time the key is depressed. But this is just a temporary setup until [Todd] could help guide his young one through some circuit design and assembly.

The replacement is based on a 555 timer. They grabbed an electronics project book and found the schematic along with a Morse code primer. With parts in hand [Todd] films as his son hones his soldering skills with each connection. The finished project uses the timer chip to produce the audio frequency heard from the on-board speaker. If you’ve never had the joy of teaching a kid how to solder, you’re going to love seeing the video.

Continue reading “You Might Be A Geeky Dad If: Your Kids Practice Spelling In Morse Code” →

A Clockwork Useless Machine Prototype

May 8, 2012 by Jeremy Cook 7 Comments

Most of us have seen the [Useless Machine] where a switch is flipped and a finger comes out to turn it off, retreating into it’s box again. Most of those are electrical, but why not a [Useless Machine] made only of mechanical clockwork? Apparently this has been done before, but why not one more?

After some rough, sketches, and almost no research, I finally “came up with” a way to do this mechanically. A small wheel acts as the driver for the assembly, which is weighed down by a T-handle attached to a string wrapped around it. When released, this smaller wheel fully rotates causing the larger wheel to rotate up around ninety degrees then come down again. In reality, the flipped switch doesn’t reverse the motion of the finger at all, it instead stops it from cycling over and over. The video after the break may explain it a bit better.

This machine currently is a prototype. Although it works well without a lid on at simply reversing the switch, it’s much too fast and isn’t capable of lifting any sort of weight. Like a lid to come out of, for instance. This whole assembly was made possible with my CNC router and inexpensive/easily machineable MDF. Continue reading “A Clockwork Useless Machine Prototype” →

Retrotechtacular: The Blit Has Given Me Access To The Power Of Multiprogramming!

May 4, 2012 by Mike Szczys 16 Comments

We normally try to be descriptive with our titles. But when that statement pops out of the narration with notable excitement it made us chuckle. This installment of Retrotechtacular is a promotional video for the Blit. It’s a graphics-based hardware terminal for Unix systems. It’s biggest boast is the ability to run (and display on screen) several different programs at once — an activity called multiprogramming. But there is also the “digitizing mouse”. On board is a 68000 microcprocessor 256k of RAM (they call it a quarter meg), and connects via RS232. The screen is 800 by 1024; that’s right, it’s a portrait orientation.

Notable in this episode are some classic eyeglass frames, and rad synthesizer sounds for scene transitions. Whatever happened to videography technique that uses a dimwitted companion to ask that all-knowing narrator stupid questions?

Continue reading “Retrotechtacular: The Blit Has Given Me Access To The Power Of Multiprogramming!” →

A Fantastic Acrylic Light Display

May 3, 2012 by Brian Benchoff 5 Comments

As a retired industrial designer, [Dave] has a lot of time to do what we’d all like to do: sit around in a workshop and make stuff. His latest project, an acrylic light display of an Indian motorcycle looks fantastic and betrays his designer heritage.

The base of the light display is made up of a laminate of a few 1/4″ pieces of Poplar carved on [Dave]’s CNC machine. These pieces were glued together with a slot routed into the top for the arcylic panel. Instead of going with a few LEDs for the light source, [Dave] used a small cold cathode fluorescent lamp with the requisite inverter tucked away inside the base. This is the same setup he used in an earlier project, and judging from that the Indian motorcycle display looks great on the inside.

After giving the wooden base a few coats of lacquer, [Dave] milled a piece of acrylic with an Indian motorcycle motif he created himself. It’s a great piece of work, sure to brighten up his very awesome workshop.

Retrotechtacular: Introducing The Brand New Acorn Risc Machine

May 2, 2012 by Mike Szczys 17 Comments

Get ready to be swept off your feet by this Acorn Risc Machine promotional video from the Mid-1980’s (also embedded after the jump). We’re sure most have put it together by now, but for those slower readers, this is the introduction of ARM processors.

The video has a bit of everything. There’s a deadpan narration with just a bit of British accent around the edges. But that’s spiced up considerably by the up-beat synthesizer track playing in the background. You’ll see plenty of programmers in short-sleeve dress shirts, and we challenge you to count the number of mustaches that make it on camera. But jest aside, it’s fun to think of how the advent of this chip affected the world.

This post is just the second installment of our Retrotechtacular series (here’s the inaugural post). We haven’t seen any old movies come in from readers yet. What are you waiting for? Digitize that footage because we want to see it! Of course it doesn’t have to be your own movies, so anything you come across that covers decades-old tech is fair game.

Continue reading “Retrotechtacular: Introducing The Brand New Acorn Risc Machine” →

Coating Technique Makes Glass You Can’t See

April 26, 2012 by Mike Szczys 24 Comments

Some of the deep thinkers over at MIT have come up with an interesting hack for ordinary glass. If you coat it in a special way it becomes nearly invisible. This is only one of the effects of the coating, but brings images of people walking through glass walls to our minds.

Joking aside, this is really very useful. The images above show a microscopic view of the cones that are applied during the coating process. They prevent the surface tension on a drop of water from being broken, and you can see the clip of water actually bouncing right off the glass in the video after the break. This also means it acts as a non-stick coating for dirt, grime, and even fog. Anyone who’s taken a tropical vacation will know that taking a picture outside with a camera that’s been in an air-conditioned room results only in a snapshot of a foggy lens. This coating could change that. But it’s also got a lot of potential with the glass panes covering solar cells. If they can’t get dirty, and there’s virtually no glare, you should see a performance boost. It’ll be interesting to see how long this takes to come to market and what the first products to use it might be.

Continue reading “Coating Technique Makes Glass You Can’t See” →