Technabob » electromagnetic

DARPA Suppresses Fire with Magic Wand

Technabob — Sun, 22 Jan 2012 23:00:34 +0000

There are lots of ways to put out a fire, but most of them require some way to actually spray or douse the flames with the suppressant. This can cause problems in small or obstructed spaces. It’s this limitation that got DARPA (the Defense Advanced Research Projects Agency) thinking about a novel way to put out a fire on contact.

Demonstrated in the video below – albeit on a very small fire – their system manages to snuff out a flame by destabilizing the fire by playing with electromagnetism and acoustics. While the DARPA program that drove the experiment aims to extinguish fires instantly, this technique does take a few seconds to kill these small methane flames.

It’s unclear exactly how it works, and there’s no evidence that they could scale it up to put out larger fires with the same technique. Still, it’s kind of magical how they just wave that little wand over the flames, and it puts them out for good.

[DARPA via Geekosystem]

Allergic to Wi-Fi? Go to West Virginia

Conner Flynn — Fri, 16 Sep 2011 11:30:49 +0000

The condition called Electromagnetic Hypersensitivity (or EHS for short) is pretty controversial. If you believe that it exists, then symptoms might include headaches, skin burning, muscle twitching and chronic pain. Those who believe they are afflicted by it blame it on exposure to electromagnetic fields from mobile phones, Wi-Fi and other equipment.

Others are not so sure this condition even exists. Maybe there is something to it, or maybe it is Psychosomatic. Either way, about 5% of Americans believe they suffer from it. And they have now found relief in the form of a place where they can be free of electromagnetic fields. That place is Green Bank, West Virginia, a certified radio-free zone. It’s part of the US Radio Quiet Zone, where wireless is banned across 13,000 sq miles. This prevents transmissions from interfering with radio telescopes in the area.

I don’t know if EHS is a real illness or not. This world is full of strange things and it works in mysterious ways, so I wouldn’t dismiss is completely. I just hope they don’t all drop their tin-foil hats at the border on the way in and make a big mess, because the place looks lovely.

[via BBC]

Rfiddler: Rfid Zapper Gun Terminates Rfid Tags for Good

Technabob — Wed, 23 Dec 2009 02:43:05 +0000

This badass looking weapon won’t hurt a fly – but it will kill any RFID tag you point it at. The Rfiddler gun can be aimed at unsuspecting RFID tags and destroy their data by simply overloading the tags with a very strong electromagnetic field.

Codeninja built this device using a Nerf N-Strike Recon CS-6 loaded up with a 0.6 kilojoule camera flash driving a 50-turn copper spool. Now I have no idea how that works, but it sure sounds nasty. Also under the hood is an MP3 player with a 2-watt amplifier and speaker to crank out some good destructo sounds when the RFID eraser is engaged. As an added bonus, the Rfiddler momentarily blinds those who stand in front of it with a bright flash.

Click to View Embedded Video Clip

Apparently, it’s also strong enough to kill many USB flash drives. Given the way this thing works, I wouldn’t aim it at your credit cards, hard drives (or the cat) either.

[via Hack A Day]

War on Wires Update: Witricity Developing Wireless Power Using Magnetic Resonance

Lambert Varias — Sat, 25 Jul 2009 06:32:21 +0000

Wouldn’t it be neat to be able to have WiFi-like access to electricity? While wireless power is by no means a novel concept – Thomas Edison and Nikola Tesla already explored the possibility of wireless power - US-based company WiTricity claim that they have one of the most feasible methods of making the world a lot more wireless. In fact, WiTricity chief executive Eric Giler said in an interview with BBC that their technology may even be in use as early as one or two years from now. Of course all of this is dependent on a lot of factors – the cooperation of electronics manufacturers for one – but it seems that Physics is on WiTricity’s side as well.

The image above shows how coils connected to a power source and to devices facilitate the transfer of electromagnetic waves that are then used to power the device. The technology is based on the work of MIT physicist Marin Soljacic, and other scientists are giving it a thumbs up, not just for its feasibility or efficiency, but for its safety. According to Professor Peter Main at the Institute of Physics in UK, electromagnetic waves are harmless as long as they’re transferred at the right frequency. Unless you’re Wolverine, in which case you’re screwed. Here’s a demo of WiTricity’s technology:

Click to View Embedded Video Clip

Man, I hope I don’t die before all of these awesome technologies go mainstream. Except for Raytheon and their ray gun. I hope that project fails.

Reporter Subjected to Heat Ray

Technabob — Mon, 02 Apr 2007 16:34:21 +0000

For some time now, there’s been buzz about the Military working on a new “crowd control system” which works by blasting people with an invisible, yet highly uncomfortable electromagnetic blast. Well it turns out that they did a little demonstration of the weapon on some members of the press back in January, and here’s a clip of the reaction of one such test subject:

Click to View Embedded Video Clip

The device, known as the Active Denial System (which probably refers to the fact that the Military will actively deny using it if it ever comes to real world use) hits its victims with a non-lethal blast of EM radiation at a range of up to 500 yards away.

The waves are said to excite water molecules in your skin to a rather uncomfortable temperature of around 55