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

sketch of f117 fighter flying

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 How could a relatively unsophisticated army using outdated soviet technology take down one of the most advanced war planes in the world?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?

radioshackThe 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.

Ask Hackaday: Global Energy Transmission – Can It Work?

global transmission logo with earth in the background

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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The iFind Kickstarter Campaign Was Just Suspended

Don't
A little more than one month ago we featured a Kickstarter campaign that was raising quite a lot of eyebrows and over half a million dollars. This particular product was a battery-free tag meant to be attached to anything you may lose in your daily life. It was supposed to communicate with Bluetooth Low Energy (BLE) devices and have a 200ft (60m) detection range.

The main claim was that the iFind could harvest enough power from existing RF fields inside a typical home environment to operate for centuries. As Kickstarter just cancelled its funding a few minutes ago it seems that the basic maths Hackaday did a while ago were correct and that the project was in fact a scam. We’ll direct our readers to this particular comment that sums up all the elements pointing to a fraudulent campaign and show you the email that the backers received:

A review of the project uncovered evidence of one or more violations of Kickstarter’s rules, which include:

  • A related party posing as an independent, supportive party in project comments or elsewhere
  • Misrepresenting support by pledging to your own project
  • Misrepresenting or failing to disclose relevant facts about the project or its creator
  • Providing inaccurate or incomplete user information to Kickstarter or one of our partners

Putting aside this news, this campaign’s cancellation raises a bigger question: why didn’t it happen before and how could we control Kickstarter campaigns? On a side note, it’s still very interesting to notice the nearly religious fervor of the sunk cost fallacy that such campaigns create in their comments.

Thanks [Rick] for the tip!

Ask Hackaday: Program Passes Turing Test, but is it Intelligent?

turing test program screenshot

A team based in Russia has developed a program that has passed the iconic Turing Test. The test was carried out at the Royal Society in London, and was able to convince 33 percent of the judges that it was a 13-year-old Ukrainian boy named Eugene Goostman.

The Turing Test was developed by [Alan Turing] in 1950 as an existence proof for intelligence: if a computer can fool a human operator into thinking it’s human, then by definition the computer must be intelligent. It should be noted that [Turing] did not address what intelligence was, but only tried to identify human like behavior in a machine.

Thirty years later, a philosopher by the name of [John Searle] pointed out that even a machine that could pass the Turing Test would still not be intelligent. He did this through a fascinating thought experiment called “The Chinese Room“.

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Ask Hackaday: Can Battery-Free Bluetooth Item Locating Tags Exist?

iFind Tag

[Vishak] tipped us about the iFind Kickstarter campaign, a 1.25×1.06×0.09″ (32x27x2.4mm) tag meant to be attached to anything you may lose in your daily life. This device communicates with Bluetooth Low Energy (BLE) enabled smartphones, has a 200ft (60m) detection range and a loud alarm. What is interesting to mention is that this device doesn’t need any battery to operate as it

recycles electromagnetic energy and stores it in a unique power bank.

As you can guess, this particular claim intrigued the Hackaday team given that we never featured so small energy harvesting devices. The ‘closest’ thing that comes to our minds is the Allsee project, a simple gesture recognition device that uses existing wireless signals (TV and RFID transmissions) to extract any movement that occur in front of it. However the antenna was quite big and very little power was extracted.

A quick Google search let us know that Bluetooth Low Energy solutions usually consume an idle current of around 10uA @ ~3V. The (very) successful Sticknfind campaign which promoted the same battery-enabled product claimed a one year autonomy with a CR2016 battery and a 100ft range, leading to a ~90mAh/24/30.5/12 = 10.2uA idle current. As we’re not expert on the subject, we would like to ask our readers if they ever came across such energy harvesting performances (3V*10.2uA = 30uW) in a normal home environment. Our very bad maths indicate that if one would like to extract power from a typical Wifi router located 2 meters from you emitting 0.5Watts of power (in a perfect vacuum environment) with a 32*27mm = 864mm = 0.000864m² tag you’d only be able to get 0.5 * (0.000864/(4*pi*2*2)) = 8.6uW.

It is therefore too bad that we can’t see in the presentation video what is inside the iFind, nor more details about the patent pending technologies involved. We hope that our dear readers will enlighten us in the comments section below.

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