Building A CRT And Bathing Yourself In X-rays

July 12, 2012 by 15 Comments

For the Milan design week held last April, [Patrick Stevenson Keating] made a cathode ray tube and exhibited it in a department store.

The glass envelope of [Keating]’s tube is a very thick hand-blown piece of glass. After coating the inside of the tube with  a phosphorescent lining, [Keating] installed an electrode in a rubber plug and evacuated all the air out of the tube. When 45,000 Volts is applied to the electrode, a brilliant purple glow fills the tube and illuminates the phosphor.

Since the days of our grandfathers, CRTs have usually been made out of thick leaded glass. The reasoning behind this – and why your old computer monitor weighed a ton – is that electron guns can give off a substantial amount of x-rays. This usually isn’t much of a problem for simple devices such as a Crookes tube and monochrome CRTs. Even though [Keating] doesn’t give us any indication of what is being emitted from his tube, we’re fairly confident it’s safe for short-term exposure.

Despite being a one-pixel CRT, we can imagine using the same process to make a few very interesting pieces of hardware. The Magic Eye tube found in a few exceptionally high-end radios and televisions of the 40s, 50s, and 60s could be replicated using the same processes. Alternatively, this CRT could be used as a Williams tube and serve as a few bits of RAM in a homebrew computer.

You can check out the tube in action while on display after the break, along with a very nice video showing off the construction.

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Flying Batman Is A Load Of Bull

July 12, 2012 by 36 Comments

Batman’s ability to fly is a falsehood. Or at least so says science. We didn’t know science was into disproving super-hero movies (that’s a deep well to drink from) but to each his own. But back in December the Journal of Physics Special Topics took on the subject with their scholarly paper entitled Trajectory of a Falling Batman. The equations presented in the two-page white paper may be above your head, but the concepts are not.

It’s not that Batman can’t fly in the way explained in the film. It’s that he can’t land without great bodily harm. By analyzing the cape in this frame of the film, researchers used Batman’s body height to establish wing span and area. The numbers aren’t good. Top speed will reach about 110 km/h with a sustained velocity of 80 km/h. That’s 80 mph at top speed and just under 50 mph when he comes in for a landing.

Oh Batman, how you’ve let us all down. If you liked this paper, you should dig through the archives. We always wondered if [Bruce Willis] could have actually saved the world from an asteroid.

[via Dvice]

[Todd] Literally Debugs This Printing Calculator

July 12, 2012 by 13 Comments

This printing calculator is a thrift store find. [Todd Harrison] picked it up for a measly $3, and it still works! But the device is about twenty years old and he thinks it’s time to clean up the aging hardware.

After cracking open the case he digs out some of the stuff that has made its way inside. This includes a few dried up moths (debugging complete). While everything is open he gives a tour of the components. The calculator has a VFD which is definitely worth the price tag of the unit even if you just want to reuse the display in another project. But that’s not all. The printing head would be a fun thing to play with as well. We could see using this in projects similar to some of the thermal printer hacks we’ve seen.

When put back together, and given a new ink ribbon, the unit is ready for another 10-years of holding down one corner of your desk. Don’t miss [Todd’s] tear-down and clean-up video after the break.

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Reading Bar Codes With Arduino And Unaltered CueCat

July 12, 2012 by 11 Comments

[Damcave] decided to try out some bar code reader projects. He got his hands on a CueCat years ago. The problem is that it outputs encrypted character sets instead of a clear text string. To get around this he used his Arduino to decrypt the CueCat’s data output.

Originally you could get you hands on a CueCat for free. It was meant to work like QR codes do now — you see a bar code, you scan it to get to a web address. It never really took off but you can still get your hands on one for about twelve clams. We’ve seen projects that clip a pin on the processor to disable to encryption. But [Damcave] didn’t want to mess with the hardware. Instead he connected the Arduino via the PS/2 connector and used software to translate the data. The encryption format has long been know so it was just a matter of translating the steps into an Arduino function.

Energia Brings Arduino IDE To The TI Launchpad

July 12, 2012 by 40 Comments

The Arduino IDE is an abstraction layer for the AVR chip which the board is based around. So it’s no surprise that it is now possible to use the Arduino IDE with the TI Launchpad board. This makes it dead simple for beginners to play around with the inexpensive and low-power MSP430 platform. This is all thanks to a lot of hard work on part of the Energia developers.

The project branches from Arduino so the look, feel, and function are all about the same. Most notably, the color scheme has migrated to red to match the board color of the Launchpad. You can configure the hardware the same way by selecting a COM port and target board. Almost everything is already working, but you should check the known issues page so that you don’t try to use a function that hasn’t been ported. Right now the list includes the random and random seed functions, as well as tone, notone, and micros. There is also an issue with analogWrite; it will only produce half the requested frequency and duty cycle can only be set from 0-50%. Still this is a great development if you’re most comfortable working from this IDE.

Nyan Fax Brings The Celebrity Kitty To Your Office

July 11, 2012 by 20 Comments

Internet blocked at your office and feel like you’re just not getting your fix of Nyan Cat? Don’t worry, you can now use the fax machine to get your fix. [Tom Scott] put together the project to our delight, which will work best if you can find one of those fax machines that uses the continuous roll of paper. But as you can see above, individual sheets will work too. The best part is that Nyan Fax is live for callers from the UK and internationally!

The hack is using something called ‘fax polling’. It allows the sender to set up an on-demand server where any caller will be sent a queue of documents. In this case [Tom] crafted a Nyan Cat document that never ends… you’ll need to disconnect the phone line or pull the pug to stop the printing. See for yourself in the clip after the break. If you’re interested in setting up your own it can be done with the mgetty and sendfax packages on a Linux box.

Just in case you’re keeping score, [Tom Scott] is one of the guys behind the Webcycle.

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Solar Oven Built To Last

July 11, 2012 by 18 Comments

The problem with most solar ovens is that they’re flimsy builds that will stand up to only a handful of uses. But this one stands apart from that stereotype. It’s big, sturdy, and used a lot of math to efficiently gather the sun’s energy when cooking food.

This is the third version of the build and each has included many improvements. The obvious change here is a move from aluminum reflectors to actual mirror reflectors. These attach at a carefully calculated angle to get the most power from the rays they are redirecting. The orange mounting brackets for the mirrors also serve as a storage area for transport. The rectangular reflectors fit perfectly between them (stacked on top of the tempered glass that makes up the transparent side of the cooking chamber).

The body of the oven doesn’t track the sun and one of the future improvements mentions adding tilt functionality to the base. We’d suggest taking a look at some of the solar tracking setups used for PV arrays.

[Thanks John]