logo if acdc band

Ask Hackaday: Who Wants An All DC House?

Sometimes when working on a righteous hack, we get goosebumps while watching our code execute faster than we could ever possibly comprehend. Seeing the pixels of the LCD come alive, hearing the chatter of relays and the hum of fans…it’s an amazing thing what electricity can do. And it is equally amazing when you realize that it all started one hundred and thirty five years ago, when [Thomas Edison] changed the world forever with the first practical electric light bulb.

That bulb was lit by a Direct Current – the same thing that runs the computer you’re reading this article on. The same thing that runs many of the hacks you read about here on Hack a Day, and almost all electronic devices in your house. But somewhere in the mix must exist a device that changes the Alternating Current from your wall outlet to the needed DC. Why? Why is it that we transport electricity as AC only to convert it to DC in our homes? You might answer:

“This argument was played out in the War of Currents back in the 1880’s.”

Indeed, it was. But that was a long time ago. Technology has changed. Changed so much to the point that the arguments in the War of Currents might no longer be valid. Join us after the break, where we rehash these arguments, and explore the feasibility of an all DC environment.

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Ask Hackaday: Can Paper USB Business Cards Exist?

swivel business card

The swivelCard Kickstarter campaign recently received a lot of press coverage and makes some impressive claims as their goal is the development of USB and NFC business cards at a $3 unit price. While most USB-enabled business cards we featured on Hackaday were made of standard FR4, this particular card is made of paper as the project description states the team patented

a system for turning regular paper into a USB drive.

As you can guess this piqued our interest, as all paper based technologies we had seen until now mostly consisted of either printed PCBs or paper batteries. ‘Printing a USB drive on regular paper’ (as the video says) would therefore involve printing functional USB and NFC controllers.

Luckily enough a quick Google search for the patents shown in one of the pictures (patent1, patent2) taught us that a storage circuitry is embedded under the printed USB pads, which may imply that the team had an Application-Specific Integrated Circuit (ASIC) designed or that they simply found one they could use for their own purposes. From the video we learn that ‘each card has a unique ID and can individually be programmed’ (the card, not the UID) and that it can be setup to open any webpage URL. The latter can even be modified after the card has been handed out, hinting that the final recipient would go to a ‘www.swivelcard.com/XXXX” type of address. We therefore got confused by

Imagine giving your business card with pictures, videos, presentations, and websites for the recipient to interact with!

paragraph that the project description contains.

This leads us to one key question we have: what kind of USB drive can make a given user visit a particular website, given that he may have Linux, Windows, Mac or any other OS? They all have similar USB enumeration processes and different key strokes to launch a browser… our wild guess is that it may be detected as storage with a single html file in it. Unfortunately for us the USB detection process is not included in the video.

Our final question: Is it possible to embed both USB and NFC controllers in a thin piece of paper without worrying about broken ICs (see picture above)? NFC enabled passports have obviously been around for a long time but we couldn’t find the same for USB drives.

Possible or not, we would definitely love having one in our hands!

Edit: One of our kind readers pointed out that this campaign actually is a re-launch of a failed indiegogo one which provides more details about the technology and confirms our assumptions.

Ask Hackaday: Floating To Space

floating into space book cover

On a cool September morning just west of Sturbridge, Massachusetts, a group of MIT students launched a low-budget high altitude project that would go on to gain global attention. They revealed to the world that with a small weather balloon, a hacked camera, cheap GPS phone and a little luck, you could get pictures that rival those from the Space Shuttle. Their project set forth a torrent of hackers, students, kids and parents the world over trying to copy their success. Many succeeded. Others did not.

At 100,000 feet or about 20 miles up, it’s a brisk 60 degrees below zero. The atmosphere at this height is but a fraction of its density at sea level. Solar radiation rains down like a summer squall, and the view is just short of breathtaking. It seems so agonizingly close to space that you could just reach out and touch it. That one could almost float right on up into orbit.

Sound impossible? Think again. A little known volunteer based company operating out of California is trying to do just this.

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sketch of f117 fighter flying

Ask Hackaday: How Did They Shoot Down A Stealth Aircraft?

It was supposed to be a routine mission for U.S. Air Force Lt. Col. Darrell P. Zelko, a veteran pilot of the 1991 Gulf War. The weather over the capital city of Serbia was stormy on the night of March 27th, 1999, and only a few NATO planes were in the sky to enforce Operation Allied Force. Zelco was to drop 2 laser guided munitions and get back to his base in Italy.

There was no way for him to know that at exactly 8:15pm local time, a young Colonel of the Army of Yugoslavia had done what was thought to be impossible. His men had seen Zelco’s unseeable F117 Stealth Fighter.

Seconds later, a barrage of Soviet 60’s era S-125 surface-to-air missiles were screaming toward him at three times the speed of sound. One hit. Colonel Zelco was forced to eject while his advanced stealth aircraft fell to the ground in a ball of fire. It was the first and only time an F117 had been shot down. He would be rescued a few hours later.

How did they do it? How could a relatively unsophisticated army using outdated soviet technology take down one of the most advanced war planes in the world? A plane that was supposed be invisible to enemy radar? As you can imagine, there are several theories. We’re going deep with the “what-ifs” on this one so join us after the break as we break down and explore them in detail.

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Ask Hackaday: What Can Save RadioShack?

The news for RadioShack is not good. The retail chain that we hackers hold near and dear to our hearts is in financial trouble, and could go under next year.  With just 64 million in cash on hand, it literally does not have enough capital to close the 1,100 stores it planned to in March of this year.

On May 27th, 2011, we asked you what RadioShack could do to cater to our community. They listened. Most of their retail stores now carry an assortment of Arduino shields, the under appreciated Parallax (why?), and even El Wire. Thanks to you. You made this happen.

Today, we are asking you again. But not for what RadioShack can do better. We’re asking what they can do to survive. To live. It makes no sense for RadioShack to compete in the brutal cell phone/tablet market, and makes every bit of sense for them take advantage of the rapidly growing hacker/builder/maker what-ever-you-want-to-call-us community. Let’s face it. We’re everywhere and our numbers are growing. From 3D printers to drones, the evidence is undeniable.

With 5,000 retail stores across the USA, they are in a perfect position to change their business model to a hacker friendly one. Imagine a RadioShack down the road  that stocked PICs, ARMs, Atmels, stepper motors, drivers, sensors, filament….like a Sparkfun retail store. Imagine the ability to just drive a few miles and buy whatever you needed. Would you pay a premium? Would you pay a little extra to have it now? I bet you would.

Now it’s time to speak up. Let your voices be heard. Let’s get the attention of the RadioShack board. You’ve done it before. It’s time to do it again. Hackers unite!

 

Ask Hackaday: Graphene Capacitors On Kickstarter

Last week, we heard of an interesting Kickstarter that puts a capacitor and charging circuit in the same space as a AA battery. This is usually a very simple endeavour, but this capacitor has the same energy density as an alkaline cell. The chemistry inside this capacitor was initially attributed to lithium ion, and a few people in the comments section were wondering how this was possible. The math just didn’t seem to add up.

The guy behind this Kickstarter, [Shawn West], recently spilled the beans on these… interesting capacitors. Apparently, they’re not lithium ion capacitors at all, but graphene capacitors. Graphene capacitors you can buy. On Kickstarter. Graphene capacitors, also known as the thing that will change everything from smartphones to electric vehicles, and everything in between. I will admit I am skeptical of this Kickstarter.

Apparently, these graphene supercaps are in part designed and manufactured by [Shawn] himself. He fabricates the graphene by putting graphite powder in a ball mill for a day, adding a bit of water and surfactant, then running the ball mill for another few days. The graphene then floats to the top where it is skimmed off and applied to a nonconductive film.

There’s absolutely nothing that flies in the face of the laws of physics when it comes to graphene capacitors – we’ve seen a few researchers at UCLA figure out how to make a graphene supercap. The general consensus when it comes to graphene supercaps is something along the lines of, ‘yeah, it’ll be awesome, in 10 years or so.’ I don’t think anyone thought the first graphene capacitors would be available through Kickstarter, though.

I’m a little torn on this one. On one hand, graphene supercaps, now. On the other hand, graphene supercaps on Kickstarter. I’m not calling this a scam, but if [Shawn]’s caps are legit, you would think huge companies and governments would be breaking down his door to sign licensing agreements.

Post your thoughts below.

global transmission logo with earth in the background

Ask Hackaday: Global Energy Transmission – Can It Work?

Atop a small mountain in Colorado Springs sat the small, makeshift laboratory of Nikola Tesla. He chose this location because the air was thinner, and therefor more conductive. Tesla had come to believe that he could use the Earth as a conductor, and use it to send electrical power without the need for wires. Though some facts are forever lost, it is said that on a clear, moonless night, Tesla flipped the switch that fed millions of volts into a large coil that towered high into the air. He cackled maniacally as an eerie blue corona formed around the crackling instruments, while some 200 florescent bulbs began to glow over 25 miles away.

A magnificent feat took place in the hills of Colorado that night. A feat that surely would change the world in how it harnessed electricity. A feat that if brought to its full potential, could provide wireless power to every point on the globe. A feat that took place almost one hundred and twenty years ago…

 

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