Build Your Own HERF Gun

James writes "Rostislav Persion from Voltage Labs has successfully constructed a HERF gun (a device like EMP but directional) in his home that is capable of stalling cars at a distance and crashing computers as well. He has videos of the device in action as it lights up LED's at a distance and triggers motion detectors. Theres also a bunch of other security stuff and science stuff which is quite interesting and controversial, such as cell phone tracking, mood altering audio signals, gyro guns, and other things of this nature. The site owner was also featured in US News Magazine and MTV for some of his work."

Comments

Re:magnetron?

[BigBlockMopar]

Magnetrons are the main component of microwave ovens. Beware -- unshielded units are dangerous. You can end up sterile, or dead... or both.

Oh my god.

Before the dot-com meltdown, I used to design radar equipment for a major defense contractor. Radar systems use microwave energy - which is just radio waves within an arbitrary range that we call "microwave", like we call some radio waves "VHF" and others "UHF".

A microwave oven is simply a ~500W unmodulated carrier wave at ~2.4GHz. Neither the power nor the frequency is terribly precise.

A magnetron is a vacuum tube used to generate microwave-frequency RF. It's a special kind of directly-heated diode surrounded by a very strong magnet, hence the term "magnetron".

It is utterly and completely harmless (except to magnetic media and the magnetic stripe on your security pass, from personal experience) until you apply power. Typically, a microwave oven magnetron wants about 6V to light the filament and about 6kV anode; in pulsed navigational radar, it's usually 6V to light the filament and about 10kV to pulse the magnetron in 25kW 12GHz pulses at 3kHz (think of AM modulation).

If you take a direct blast from a radar, it's unlikely to make you sterile, or to cause cancer. Those are caused by ionizing radiation (ie. nuclear and X-Ray). This is non-ionizing; essentially just a radio wave. In the S and X band radar ranges - and presumably everything in between - the primary damage would be to the corneas of the eyes. And it burns - I got it to my torso once, no permanent damage, just like a bad sunburn.

In other words, don't operate your microwave oven with the door open, and don't look into the waveguide.

Oh, and don't play with the power supply which runs the magnetron. Anything capable of supplying enough current to make 500W at 6kV (ie. power supply of a home microwave oven) is capable of setting fire to your skin. And the capacitors in a microwave oven hold a charge for a while - don't play with them.

Cached Page

[randomErr]

SITE URL 01: www.VoltsAmps.com
SITE URL 02: www.VoltageLabs.com
SITE URL 03: www.SVBxLABS.com

Purpose:

This project is a continuation of the HERF003 project. It will be just like the HERF001 but many times more compact and efficient due to optimization and better calculated design. The actual device (excluding the horn antenna) will be about 50 times smaller in volume than HERF001 while having the same output power yet even better antenna efficiency and low VSWR. I hope to get much more detailed tests done on the effects and range of this device. Results and test images/videos will be posted allong with data sheets, radiation patterns and videos of test shots on dummy PC's.

Materials:

- 800W 2.458GHz Magnetron
- MOT
- 2kV @ 1.2uF capacitor
- 12kV piv microwave oven diode
- Sheet metal
- Sheet copper
- Other small parts

Details:

This is the basic magnetron coupling design. It is designed after the WR340 waveguide and can allow 1.70GHz to 2.60GHz to pass through with low attenuation. Of course my RF output will be within this range being 2.458GHz. The full dimentions of the waveguide are 4.318cm x 9.147cm x 8.636cm. The horn antenna is not as small as pictured. The magnetron feed will be inserted 1/4 the wavelength from the back of the waveguide.

a = 86.36mm
b = 43.18mm
c = 91.47mm

For a 15dB horn antenna:

p = 152.5mm
a1 = 320.6mm
b1 = 237.5mm

For a 18dB horn antenna:

p = 365.9mm
a1 = 452.9mm
b1 = 335.5mm

These are the dimentions of the plates that must be cut out in order to form a 15dB horn antenna.

These are the dimentions of the plates that must be cut out in order to form a 18dB horn antenna. Of course two of each plate must be made in order to make a complete horn antenna. The back end is then welded to the waveguide.

This is the circular waveguide and conical horn and its dimentions. The distance between the magnetron feed and the back waveguide wall should be fine tuned and adjusted as needed. The waveguide diameter is 3/4 the 2.458GHz wavelength and the distance from the magnetron feed and the base of the horn is 1/2 the wavelength.

This is the schematic of the HERF004 if powered from a 120VAC (or 240VAC) source. The circuit consists of a transformer and a voltage doubler cap/diode setup. A filiment heater is also needed.

This is the schematic of the HERF004 if powered from a 12VDC battery source. This design will provide less average RMS output power but will provide the same if not higher pulse peak power. Most magnetrons have the markings F, FA, C, or K next to the leads of which F, C and K are the magnetron cathode. Most microwave oven magnetrons will be marked with FA and F while radar magnetrons will only have one lead marked with either a K or a C. Since the magnetron I am planning to use is not a pulsed magnetron I will not construct a pulse forming network although it would help.

Videos:

herf004-test001.mpg (8.03MB)

This clip shows a series of herf004 shots at different distances. The video clip contains both video and audio. In the audio you can hear the 60Hz hum as it was induced into the camera via 2.458GHz carier wave.

herflight01.mpeg (0.98MB)

This clip shows HERF004 exciting the gas within a flourecent light tube causing it to glow.

herfmotion01.mpeg (0.97MB)

This clip shows HERF004 triggering the driveway motion detector of my home and the house next door.

Images:

This is the horn right after its construction. I cut it out of sheet copper and then welded each sheet together. My welding skills weren't that great so the plates may be misaligned by upto 4mm. The horn was designed to be 17dB since my sheet copper wasn't large enough to make an 18dB horn. I will probably make a conical horn after this one though and use it instead since this one turned out to be quite large.

First HERF004 victim, me. As I was drilling a hole for the magnetron feed the