If you’ve already dipped your toes into high-voltage power supply pool you may be thirsty for a bit more knowledge. Here’s a neat illustration of how to build a voltage multiplier that can output a positive or negative supply. It is based on a design known as the Cockroft-Walton Multiplier. It’s the add-on housed in the plastic box seen in the image above. It uses diodes and capacitors in an orientation very common for generating high voltages. In fact, the same thing can be found in that high-voltage bulletin board. The place this differs is when it comes to connecting the multiplier to the PSU.

If you look closely you can see one red and one black banana plug jack poking out the end of the plastic container. There is also a pair of these on the other end. The multiplier has been designed so that reconfiguring the inputs and outputs changes how it works. Each jack has been labeled with one possible input and one output. Choose the desired output (DC+ or DC-) and then follow the labels for the rest of the connections.

What can you do with this setup? Check out the clip after the break that shows it powering a lifter.

[Grenadier] built his very own x-ray machine. He’s no stranger to high voltage – we’ve seen his Jacob’s Ladders and Marx generators. Surely he can handle himself with high voltage and dangerous equipment. With this portable x-ray machine, [Grenadier] has begun overloading Geiger counters. We’re just happy he knows what he’s doing.

The key component of [Grenadier]‘s portable x-ray machine is the Coolidge tube, a simple vacuum tube that produces x-rays with the help of 75 kilovolts of power. The finished build looks awesome. Two meters display the milliamps and kilovolts going to the x-ray tube, and a trio of nixies display the exposure time.

Even though [Grenadier] doesn’t have x-ray film, he can see through things with a scintillation screen that fluoresces when exposed to ionizing radiation. There are two pictures of the x-ray in action – one showing the inside of a pen and the guts of a hard drive (as shown in the title pic).

The output of the x-ray was measured with a Geiger counter. [Grenadier] was able to get a hit every second or so at 50 yards, and very loud white noise at 1 foot. Check out the video of [Grenadier]‘s Buildlounge laser cutter contest submission after the break.

via Buildlounge

We love a good Tesla coil music performance, but have never really considered building our own. After reading [TheHomebrewGuru's] guide to musical Tesla coils we’re still not considering it. Whether or not you’re going to undertake the project, his massive writeup is worth a look.

The tutorial begins at the beginning, with a bit of background on these devices, including what they are, where they came from, and the electrical theory behind them. From there it’s on to the build. This isn’t a go-out-and-buy it type of project. You’re going to need some ingenuity to hunt down parts that will work, and will work with each other.

The image above shows a partially built device, using sheet metal ductwork covered in foil tape as the torroid at the top. The column is wrapped in wire, forming the secondary coil, and the wooden base is ready for the installation of the primary coil. Electronics will be housed between the two wood discs of the base, with a TI Launchpad board driving the music part of the hack.

There isn’t a good demo video of this playing music. But you can get the idea if you look back at the head-mounted tesla coil which did a great job of pumping out the tunes.

We can hear the commercial now…

“Reeeeeeal men of geniuuuuuuus! Here’s to you Mr. no-fear, singing Tesla coil on your hat wearing guy…”

Call him a genius or call him crazy – all we know is that [Tyler’s] Tesla coil hat is awesome! Even though it’s the middle of November, we couldn’t pass up this Halloween costume.

[Tyler’s] creation essentially boiled down to taking a standard dual resonant solid state Tesla coil and shrinking it down to a reasonable size for mounting on his skull. The mini Tesla features a pretty compact boost core which worked reasonably well, at least for a little while. He says that the boost never truly worked properly and needs a redesign, which is something he’ll tackle when he gets some free time.

Boost issues or not, we think that the video below speaks for itself. The hat is certainly an attention getter, and we think it’s great – even if wearing a Tesla coil on your head is not necessarily the safest thing to do.

Electrical Engineers don’t need push pins. That’s because they know how to control electrons! [Sven] put his knowledge of these subatomic particles to use when building his high voltage bulletin board. It uses a set of vertically strung wires to keep paper pinned against the board. The wires have high voltage at low current travelling through them. They’re in front of the board, but not touching it, and the board is serving as a ground plane. In this way an electrostatic charge pushes (or should that be pulls?) against the paper to keep each sheet right where he places it.

In the video after the break [Sven] gives us a tour of the hardware at work here. It starts with a 12V psu which feeds a buck converter. The regulated feed is patched into a high voltage supply which was designed as a CCFL driver. Finally, a voltage doubler is used to reach the final voltage, measuring about 20 kV per wire.

Don’t worry, [Sven] says the bare wire is “almost completely safe” because of the low current being conducted.

[Matt] entered himself in a pumpkin carving contest this year, even despite the fact that his artistic skills were a bit…lacking. He knew that he had very little chance of winning the contest unless he had a great gimmick to make his creation stand out, so he started brainstorming.

[Matt] figured that since his design would have to be somewhat simple, he needed something eye catching that he could add to the pumpkin after it went under the knife. Like a bolt of lightning, inspiration struck, and he set off to fetch an ignition transformer along with some wire coat hanger.

He built a makeshift Jacob’s ladder that would fit perfectly inside his hollowed out pumpkin, and proceeded to carve the pumpkin with the “Caution, risk of electric shock” logo, familiar to most anyone that works with electronics. You can see the final result in the video below, which we think looks pretty neat. If he didn’t end up winning the contest, we’d be shocked!

Reader [Xellers] sent in his newest instructable: DIY Electron Accelerator: A Cathode Ray Tube in a Wine Bottle. While not exactly what you might think of a cathode ray tube, the basics are in place. A wine bottle is used as a vacuum chamber and a 9kv neon transformer is attached to a stopped in the top. A cathode is placed mid way, the air is sucked out with a pump, and high voltage is applied.

Naturally as more air gets pumped out the electric arc intensifies into a pretty solid plasma filling the space between the two contacts. While mixing drilled glass with a vacuum and high voltage sounds like an awesome hospital story [Xellers] does cover some safety points including the possibility of this thing putting out some nasty waves.

One thing that is not mentioned (that I saw)  is this is very similar to how florescent light tubes work and without florescent material lining the chamber it will spit out quite a bit of UV light (notice germicidal UV lights are clear). So you will want to watch your eyes!

Join us after the break for a quick video.

Over the last two weeks, we’ve seen some pretty crazy and potentially dangerous stuff, like a stun glove and modern day alchemy. For our high voltage theme finale, we couldn’t pass up [Photonicinduction]‘s YouTube channel.

Best known for his self-destructing washing machine (the source of this animated .gif), [Photonicinduction] is also the brainchild behind the hair dryer flame thrower and his homemade fifty thousand amp transformer.

While we do like his Not Safe For Work ammeter (yes, it really is NSFW), some of [Photonicinduction]‘s videos – charging a car battery in 4 minutes, making a kettle boil without a heater element, pressurizing coconuts to over 200 psi, and exploding rabbits – are hilariously dangerous and should not be attempted by anyone.

We need to say you should not attempt to emulate [Photonicinduction]‘s hijinks under any circumstances. Cleaning up a puddle of burning gasoline with a vacuum cleaner may sound like fun, but copying [Photonicinduction] will eventually get you killed. This man must know his stuff, because we’re honestly shocked he hasn’t exploded yet. The best way to enjoy three hundred thousand volts is probably grabbing a coffee and watching [Photonicinduction]‘s YouTube channel.

Normally when we hear of a Champ guitar amp, we think of a sweet-sounding rig that puts out 6 Watts through an 8-inch speaker. [John Chambers] of Champ Electronics wanted to build a true champion for the field of battle and came up with The Champ 1000 Watt Tube Amp, an amplifier that probably puts out enough heat to keep an igloo warm.

The amp is based on 807 valves. With some clever engineering [John] managed to coax 100 watts out of a pair of 807s, so the entire amp “only” requires 20 power tubes. The build log shows some pretty impressive examples of electrical prowess. We can’t recall the last time we featured a build with point-to-point wiring on tagboard, and [John]‘s work is some of the best we’ve ever seen.

[John] has been working on this amp off and on for a few years now, but he should be wrapping up the build sometime soon. We haven’t seen this amp in action, but we imagine it would look something like this 36×10 monstrosity. Send us a message or post a comment if you can find a video and we’ll put it up.

Although many might not know it, electroluminescent materials use high voltage, and thus qualify for our featured topic. Many may assume that these sheets work in the same way as LED lights, using low-voltage DC power.  This, however, is not the case, as they need around 100 volts of AC current to allow them to light up.

For a battery-powered solution, this means converting the battery’s DC power to AC. Adafruit has a good tutorial about working with EL wire and powering it up using a portable inverter. One should obviously be careful to properly insulate any clothing using this material as being shocked is generally not fun.

The video after the break is pretty long, but is well produced and will give you a good background of EL use. If you don’t have 30 minutes to dedicate to this, be sure to at least skip to 2:43 to see one of the coolest EL shirts we’ve seen.

For another related hack, check out this one by [Jeri Ellsworth] about making EL ink.

There’s a proverb that says ‘Speak softly and carry a big stick’. Now that stick can come in a high-voltage form factor. The device above, which reminds us of a side-handled baton with a coke can stuck on the end, is a portable Van de Graaff generator.

Although debated in the comments, the creator of this hack claims you can shock someone with 84 kV of electricity using the device. Of course as a weapon it’s lacking since we’re talking about static electricity; the voltage can be through the roof but the current is extremely low. Despite that, there are some fun things you can do with them. The video after the break show it throwing off sparks with the lights dimmed. [Yardleydobon] also includes a few other tricks at the end of his tutorial. He makes a set of Franklin Bells using two more soda cans with the aluminum tab from one suspended in between them. As he charges it up, the tab dances back and forth, ringing the ‘bells’ it runs into. Once they are charged, the ringing can be restarted by discharging just one of the cans.

Continuing on with our high-voltage theme, today we have a page describing Marx generators by [Grenadier]. Marx generators are devices that produce pulses of very high voltage with fast rise times. For most of us, that means that they can make neat sparks. For the more serious types out there, that also means that they are great for driving some high-powered lasers, simulating lightning strikes, and even igniting the conventional explosives surrounding the core of a nuclear weapon! His page includes a video of his Marx generator producing some pretty sparks for those of us who aren’t so serious.

We have featured several of [Grenadier's] projects in the past. This one doesn’t deviate from his normal style of taking a subject and clearly describing it with lots of well-taken pictures.

Recently, he has been working on improving one of his projects that deviates from what he normally does. He is calling it “The Junkbox”. The Junkbox is something like a free online swap meet where you can sell your electronic parts.

If you’d like to build a Jacob’s ladder, an ignition system for a flamethrower, or for some ungodly reason you need 15 kilovolts for a prop replica or cosplay build, this one is for you. It’s an easy to build high voltage power supply that interfaces with an Arduino.

After harvesting a flyback from the power board of a CRT, [Andrew Moser] added a new primary coil to the transformer. This boosts 12 volts that can be easily controlled by an Arduino to something that will arc an inch and a half. The next step building the flyback driver. [Andrew] used a MOSFET and MOSFET driver for this circuit (although he says this guy works without the driver). After that, all that’s left to do is write some software and test it out.

Of course this comes with the boilerplate warning, “If you don’t know what you’re doing, you might die.” That being said, if you ever wanted to test out an Arduino’s resistance to EMP, this is the project for you. Check out the flyback powering a Jacob’s ladder after the break.

The anthem for the Great Recession might be something along the lines of, “That we’re gonna do it anyway, even if doesn’t pay.” Some men just want to watch the world burn, so Hackerbot Labs posted a great walkthrough about shrinking coins and in the process making our pocket change worth just a little bit more.

Their build pushes 15,000 Joules (from a 10kV 300μF cap) through a coil of wire wrapped around a coin. This creates a magnetic field in the coil and the coin. These two fields repel each other, and there’s only one way that it can end: the coin shrinks and the coil of wire explodes. The team at Hackerbot Labs linked to a great theory of operations that does a great job explaining the physics has some awesome pictures.

During our research, we saw a few questions about the legality of altering currency. According to the U.S. Code, shrinking coins only illegal if it’s done fraudulently, like shrinking a penny down to the size of a dime to fool a pay phone or vending machine. Check out a video of the Hackerbot Labs setup putting as much energy as 100 heart defibrillators into a coin after the break.

Instructables user [Admiral Aaron Ravensdale] just finished a high voltage plasma bulb build that makes creative use of off-the-shelf parts. As a self-described steampunk, [Adm. Ravensdale] also earned some cred by included working gears in his build.

The heart of the build is a “flicker flame” candle light bulb. These light bulbs have two flame-shaped plates inside the bulb to act as electrodes. Instead of the Argon that normally fills an incandescent light bulb, the candle bulb is filled with Neon. When excited, Argon gives off a rather unnatural purple glow – not very convincing for a simulated candle and certainly not steampunk. The Neon in the flickering candle bulb gives off a brilliant orange, perfect for simulating a flame and will surely impress the duchess during afternoon tea.

After the right plasma bulb was found, [The Admiral] scavenged the rest of the high voltage electronics from disposable cameras. Attaching three electrodes to a brass gear, the entire mechanism was made to spin using parts from an old clock and a CD drive motor. We’re always impressed with the scavenging abilities of steampunkers – we’d still be waiting for our gears to arrive if we attempted this. Check out the video of this really cool and very inexpensive plasma bulb after the break.