[Grenadier] Had some spare wire, electrical tape, and a giant ferrite core laying about and decided to create a massive and pretty snappy looking disk shaped flyback transformer. Dubbed the Fryback, he claims that it will “revitalise your health and bring wondrous wealth and prosperity to your family”.
He chose a disk shaped transformer because they look cooler, fair enough.. (oh and they reduced inter-winding capacitance and the voltage difference between layers). The construction is fairly simple, but time consuming. Grenadier goes through the important steps on his website, but be prepared for 25 hours of winding wire if you decide to make your own.
Running at 48V the Fryback can output 8kV at a very high current, producing some nice thick 30cm long sparks. Check out the video after the break to see the Fryback in action.
Continue reading “A big transformer, because it’s cool!”
[Jeri Ellsworth] had a bright idea – a brain-activated light bulb that floats above your head. While out and about, she saw some guy with a video game icon attached to metal rod sticking out of his backpack. The rod made the icon appear to be floating above his head (think The Sims), which was the inspiration for this LED powered light bulb. The bulb is connected to a metal rod, as well as a metal hoop which is springy enough to keep a pair of electrodes snugly attached to your head.
Those electrodes, along with a third probe used for noise reference, are hooked up to a AD620 instrumentation amplifier. With the help of op amps, it modulates the red or green LEDs that are attached to the back side of the light bulb. The end result is an amusing way to show brain activity while being grilled on a Q/A panel, or while just wandering around taking in all the amazing sights presented at Maker Faire.
Join us after the break for a video demonstration.
Continue reading “A Bright Idea”
We have been featuring some home made capacitors this week, and [Mike] wrote in to share his with us. While rolled capacitors are nice, they can be somewhat difficult to construct and grow to unwieldy sizes as capacitance and voltages increase. His solution is to stack the layers up using plastic plates.
In this forum post he explains that using disposable plastic plates and tinfoil you’re able to quickly make a capacitor, that for him was valued at around 12.2nF, using eleven layers . Applying pressure to the stack capacitance grew to about 14nF, though he is having a bit of trouble holding it with just glue.
Testing was conducted with high voltages charging the capacitor up, then its leads were shorted for a nice spark and a good pop. Definitely fun for the next family cook out, though we don’t know how some left over potato salad goo would effect the end results.
[PT] just published an editorial calling on manufactures to transfer knowledge about products they are discontinuing by making them open source. He makes his case on the basis that millions of dollars and innumerable man hours go into developing these products, only to be lost when the company decides that the project is no longer (or maybe never was) profitable. We have to say he’s got a point. Granted the answer to “why not?” is that companies don’t want to give any help to their competitors. But just think of the opportunities lost to society when we can’t build on the work of others.
Now [Phillip] doesn’t stop with his plea for new policies. He goes on to list and defend a few products that are already dead and buried, for which he wishes the secrets had first been shared. These include the Palm V personal data assistant, IBM’s Deep Blue, Sony’s robotic toys/pets, and several others. For what it’s worth, we can think of one company that’s a shining example of this; the source code for Doom, which id Software released for non-profit use more than a decade ago. Good for you id!
Something new is coming to a store near you: electronic price tags. [deadbird] decided to get one and see what makes it tick. First off it just looks like an LCD with some coin batteries and a simple board, but removing the batteries it was found that the text still appeared on the screen meaning its an E-Ink display.
Close examination of the chips on board shows that this model has an ATMEL ATMEGA16L, and a ATMEL952 25128AN (a 128k eprom with SPI interface), which makes this thing possible to bend to ones will. Also, dumping the eprom with an Arduino gets everyone a bit closer to decoding the instructions this thing needs to display its graphics, similar to the HP VFD hack we posted about not too long ago.
We have not seen these yet in our local shops, but give it time and it is bound to start popping up in our favorite surplus locations soon enough.
Seeed Studios, makers of the Seeeduino and fabricators of small-run PCB orders have put out a call to help develop an open source radiation detector. Will it be of any help to people in the area of Japan that is at risk? We really can’t say. But if you can lend some expertise with this, it can’t hurt. We’ve already seen a simple dosimeter project but this one sounds like it’s more on the level of a DIY Geiger counter. We know it’s possible, but the hacked together unit we saw back in 2007 had very little documentation and used parts that may be hard to come by.
The specific information needed is what type of sensor to use, what supporting circuits should be included, and what method is best to calibrate each unit. There’s a discussion going in the comment thread of that post which should be interesting to read even if you think you don’t have anything to add.
Idle developers of the world take inspiration from this project and unite to create your own version. It’s called the Junkyard Jumbotron because it takes many different displays and allows them to be used as one big interactive display. The image above shows a collection of smartphones displaying a test pattern. The pattern is unique for each device and is used to calibrate the display. Using a digital camera, a picture of these test patterns is snapped, then sent to the server. The server calculates the position of each of the screens, then sends the correct slice of a large image back to each phone.
It’s funny that they use the word Junkyard in the name of the software. Each display needs to be able to run a web browser so you can’t just use junk displays. But one nice side effect of the hardware requirements is that you can still do things like panning and zooming as seen in the video after the break. Here’s the real question: can you make this work as an open source project? How about something that can be easily set up to work with a LAMP server?
Continue reading “Junkyard Jumbotron is begging to for an open source project clone”