HERF Gun: Make it in your basement

CuriousGeorge113 was the first one to write us about the homemade HERF gun an engineer unveiled at Infowarcon '99. All stuff that you can buy from a hardware store, and disable computers at varying range, depending on size. The current model does not do permanent damage, unlike EMP.

Comments

Its a tesla coil with a director/reflector antenna

[anticypher]

All this guy has done is built a simple pulsed DC Tesla coil using some sort of vibrator and a huge step-up transformer. Lots of people have done that, its nothing new.

He'd have to have at least three stages of RLC circuits to get an efficient power coupling into the antenna and then radiated off into the ether (maybe he has, it doesn't show in the photo). Yes, it can be done by winding your own coils, and buying an old 20kV capacitor from an electric company auction or scrap dealer. Then you would have a very effective disruptor of unprotected electronics (but not likely to cause permanent damage except with a proximity of a few inches). Making it highly directional is left as an exercise for the student ;-)

Years ago I helped tune a HUGE multi-stage step up system to duplicate the experiments of Nikola Tesla (sending spark gap morse code). This guy had built it into his garage, and had collected huge old power supplies from an old AM radio station to power it. We tested it briefly for a few seconds each evening. Whenever we worked on it, one of his cooler neighbors came over to play with it as well. Seems that every time it was switched on, all radio and cable TV reception in the area was overpowered. Fluorescent lights glowed up to 30 feet away, and nearby computers would crash.

For a few months there were cable TV trucks patrolling his neighborhood with all kinds of detecting/directional antennas looking for the source of the HERF (he kept it off most of the time), eventually they posted reward notices on phone poles in the area. He dismantled his whole setup and moved it that day (his house has never been cleaner :-). Cops came around the next day with a search warrant, didn't find anything and left. Now he only does his experiments in an old barn in the middle of nowhere, with no electical lines nearby. Any cars driving near the place stall and the CD player will skip, and he advises leaving all credit cards and watches somewhere else when visiting. I think some day he will actually discover zero-point energy or tap into the earth's natural resonance of 12Hz.

I cringe when I think of how this idea will be mutilated by the movie industry. A HERF gun that looks like an M16 or a .45 caliber pistol and shoots star-wars-like bolts of light, or the death ray in "Revenge of the Pink Panther", or the size of a packet of cigarets with some big LED numbers counting down with an audible click.

the AC

Possible use of this device

[Markee]

Everyone's afraid of a new class of terrorism that seems to be emerging. Bombing and shooting people is for dumbos. These days, smart terrorists disrupt the use of technologies like phone, cell phone and computers. This is a device for them.
Imagine this device placed near a major phone line hub... within view of a cell phone transmitter... on a highway bridge, the latest "drive-by-wire" cars passing beneath it... on an airport... at a stock exchange... Devices like this, at a handy size, could be as dangerous to economics as a gun is to an individual.
I wonder if there is a law against things like that.