Become Very Unpopular Very Fast With This DIY EMP Generator

October 12, 2016 by Gerrit Coetzee 140 Comments

Taking a break from his book, “How to Gain Enemies and Encourage Hostility,” [FPS Weapons] shows us how to build our own handheld EMP generator which can be used to generate immediate dislike from anyone working on something electronic at the hackerspace.

The device is pretty simple. A DC source, in this case an 18650 lithium battery cell, sends power to an “Ultra High Voltage 1000kV Ignition Coil” (as the eBay listing calls it), when a button is pressed. A spark gap is used to dump a large amount of magic pixies into the coil all at once, which generates a strong enough magnetic pulse to induce an unexpected voltage inside of a piece of digital electronics. This usually manages to fire a reset pin or something equivalent, disrupting the device’s normal operation.

While you’re not likely to actually damage anything in a dramatic way with this little EMP, it can still interrupt an important memory write or radio signal and damage it that way. It’s a great way to get the absolute shock of your life if you’re not careful. Either from the HVDC converter or the FCC fines. Video after the break.

Continue reading “Become Very Unpopular Very Fast With This DIY EMP Generator” →

Google Contest Builds More Efficient Inverters

March 6, 2016 by Brian Benchoff 110 Comments

A few summers ago, Google and IEEE announced a one million dollar prize to build the most efficient and compact DC to AC inverter. It was called the Little Box Challenge, with the goal of a 2kW inverter with a power density greater than 50 Watts per cubic inch.

To put this goal into perspective, the DC inverter that would plug into a cigarette lighter in your car has a power density of about 1 or 2 Watts per cubic inch. Very expensive inverters meant for solar installations have a power density of about 5 Watts per cubic inch. This competition aimed to build an inverter with ten times the power density of what is available today.

Now, the results are in, and the results are extremely surprising. The best entry didn’t just meet the goal of 50 W/in³, it blew the goal out of the water.

The winning entry (PDF) comes from CE+T Power, and comes in a package with a volume of 13.77 in³. That’s a power density of 143 W/in³ for a unit you can hold in the palm of your hand. The biggest innovations come from the use of GaN transistors and an incredible thermal management solution.

Other finalists for this competition include Schneider Electric Team from France that managed a 100 W/in³ and a Virginia Tech team that managed a power density of 61.2 W/in³.

Thanks [wvdv2002] for the tip.

FAA Bans Drones For More Than Six Million People

December 29, 2015 by Brian Benchoff 126 Comments

In recent weeks, the FAA has solicited input from hobbyists and companies in the ‘drone’ industry, produced rules and regulations, and set up a registration system for all the quadcopters and flying toys being gifted over the holiday season. Whether or not the FAA is allowed to do this is a question being left to the courts, but for now, the FAA has assuredly killed a hobby for more than six million people. The FAA has introduced an updated Temporary Flight Restriction (TFR) for a 30-mile radius around Washington, DC.

Previously, there had been a blanket ban on drones, UAS, and model aircraft within a 15-mile radius of a point inside Reagan National Airport. This point covered the District of Columbia proper, and the suburbs of Bethesda, College Park, and Alexandria – basically, everything inside the beltway, and a mile or two beyond. The new flight restriction for drones covers a vastly larger area – all of the DC metro area, Annapolis, half of Baltimore, and all of northern Virginia. This area encompasses a population of more than six million people.

The DC metro area has, since 9/11, become some of the most complex airspace in the entire country. There are several military bases, Aberdeen proving grounds, the US Naval academy, and of course the White House, Capitol building, and the Pentagon. Even commercial airliners are subject to some very interesting regulations. For the same reason general aviation shuts down in southern California every time the president visits LA, you simply can’t fly model aircraft within the beltway; it’s a security measure, and until now, flying clubs in the DC area have dealt with these restrictions.

The new TFR has effectively shuttered more than a dozen flying clubs associated with the Academy of Model Aeronautics. DCRC, a club with a field in the middle of some farmland in Maryland, has closed down until further notice. The Capital Area Soaring Association has also closed because of the TFR.

Although called a Temporary Flight Restriction, this is a rule that will be around for a while. The FAA says this restriction is here for good.

Scope Noob: Bridge Rectifier

December 3, 2014 by Mike Szczys 58 Comments

Welcome back to this week’s installment of Scope Noob where I’m sharing my experiences learning to use my first oscilloscope. Last week I started out measuring mains frequency using an AC-AC wall wart adapter. Homework, for those following along, was to build a bridge rectifier and probe the signals from it. Let’s take a look.

Continue reading “Scope Noob: Bridge Rectifier” →

Hackaday At MakeDC

March 22, 2014 by Brian Benchoff 3 Comments

makedc

Last Wednesday, our Hackaday travels took us to the Washington, DC area for a visit to NOVA Labs near Dulles and a yet-to-be opened Metro stop. Also on our itinerary was a visit to MakeDC, an informal get together for people around the nation’s capitol to show off their latest projects and builds.

The highlight of the evening was a pair of talks from [Julian] and [Taylor] on a project they did for work: a social cooler, or a locked box holding cool drinks that will only open when enough people send a text to a certain number. We’ve got [Julian]’s talk on video, but despite our fancy new camera gear for this sorta thing, [Taylor]’s demo of what an Electric Imp can do was lost to the digital wastes.

Aside from [Julian]’s talk on APIs and [Taylor]’s talk on the Electric Imp, there were a few impromptu presentations from the attendees. One of the most thorough was the duo from Shiny & Jackal Cosplay, crafters of EVA foam and LEDs. Truth be told, Hackaday doesn’t see many of these ‘softer’, cosplay and prop making builds in the tip line, and that’s a shame; the amount of skill that goes into these costumes is at least as equal as a woodsmith that can build fine furniture using only hand tools.

Perhaps a little premature, but TechShop is opening a new location in Arlington, VA at the end of the month. The GM [Addam Hall] was there scoping out the hacks and letting the attendees know there’s going to be a huge, awesome shop that’s down town in Crystal City. Close enough to public transportation, anyway, because anyone who drives in DC is certifiable.

The last item of note isn’t a build yet, but it’s shaping up to be pretty cool. It’s BRWRY – pronounced, ‘brewery’ – and will be a semi-automated beer making machine. Robots and beer, what can’t you love?

We’d like to thank [Zach], [Julian], [Taylor], and all the other guys from iStrategyLabs for putting together a nice evening of hanging out, drinking beer, eating pizza, and talking about what you’ve built. We had a great time, and we’re looking forward to the next one, as well as any other similar get together in other cities.

Searching For Makers In Washington DC

March 3, 2014 by Brian Benchoff 25 Comments

Despite there being an inordinate amount of techies and tech companies in the Washington, DC/Northern Virginia area, there aren’t really that many hacker/makerspaces, or really anywhere else for tinkering, building, and generally futzing around with a soldering iron. [Zach] thought it was time for a change and is now organizing the second Make DC an informal get together to show off your latest projects and builds. Here’s the best part: Hackaday is coming, and we’re bringing some sweet swag.

Right now [Matt] has two talks lined up focused on bringing APIs into the physical world. There’s space for plenty more speakers, so if you have something to show off be sure to sign up.

The event is scheduled for Wednesday, March 19, 6:30 PM, half a block away from the Dupont Circle Metro station. Be there. You’ll get a sticker at least.

Experimenting With Bridge Rectifers For AC To DC Power Conversion

November 20, 2011 by Mike Szczys 28 Comments

The folks over at Toymaker Television have put together another episode. This time they’re looking at bridge rectifiers and how they’re used in AC to DC converters.

This is a simple concept which is worth taking the time to study for those unfamiliar with it. Since Alternating Current is made up of cycles of positive and negative signals it must be converted before use in Direct Current circuits; a process called rectification. This is done using a series of 1-way gates (diodes) in a layout called a bridge rectifier. That’s the diamond shape seen in the diagram above.

This episode, which is embedded after the break, takes a good long look at the concept. One of the things we like best about the presentation is that the hosts of the show talk about actual electron flow. This is always a quagmire with those new to electronics, as schematics portray flow from positive to negative, but electron theory suggests that actual electron flow is the exact opposite. Continue reading “Experimenting With Bridge Rectifers For AC To DC Power Conversion” →