.:: HERF005 ::.
The purpose of this project is to construct a high quality working model of a homemade HERF device built from microwave oven components. I will be presenting this HERF demo at the 10th annual Information Warfare Conference in Washington DC on the 2nd of October, 2003. I will have to crash a running PC with it to demonstrate how effective the device is, and how simple it is to construct. I also assembled a smaller 12kW XBand version that can run on a 9 volt battery to demonstrate the difference in size and efficiency between the microwave oven version and the 12kW version. Many people can design the microwave oven HERF after getting atenna specs off my site, but a 12kW version that can fit in a shoe box takes some skill.
- 1000W 2.458GHz Magnetron
- 2kV @ 1.2uF capacitor
- 12kV piv microwave oven diode
- Sheet metal
- Control Box
- Voltage Panel Meter
- 12V Transformer with rectifier
- 12V Cooling Fan
- Light Bulb
- Other small parts
Back view of the 18dBi horn antenna after being bolted together.
Front view of the horn antenna sitting on top of the ply wood which will be cut to size as the base for the device.
Yet another angle of the antenna.
This is the unfinished HERF005 waiting on its wheel supported base to be completed.
A front view of the painted and completed device with the control panel running from it on a red cable.
The side view of the finished product shows the red warning light that turns on two seconds before the HERF begins emitting a kilowatt of microwave radiation.
This is the 12kW x-band HERF top view with no antenna connected. This HERF is able to crash a PC at a distance of about 75 meters (246 ft). The power supply consists of an inverter circuit and uses a pulse transformer to provide shaped pulses to the magnetron's cathode. All switching is solid state for improved efficiency.
herf-comp-wcase.webm (617 kB)
The HERF vs. a Compaq Pentium I, with the computer case firmly attached, at a distance of 15 feet. The PC drops out of the screen saver and begins to malfunction, while the screen flickers.
herf-comp-wocase.webm (925 kB)
The HERF vs. a Compaq Pentium I, with no side covers, at a distance of 15 feet. The PC is immediatly forced to reboot, and stays locked up until the HERF is powered down.
The 1kW HERF makes a nice demo for showing how high power microwaves can affect computer hardware however these recycled microwave oven devices consume lots of average power and transmit a continuous low power wave. For HERF the ideal is a high peak power low average power output. A good analogy for this would be breaking down a door. You can push on it lightly all day wasting energy, and the door won't break, but if you use a tiny bit of energy and release it all at once by kicking the door it will break open. HERF is about breaking semiconductor junctions and you want to induce a quick high voltage across it. The way to go is high peak power microwave sources. Using high frequency allows the antenna to be smaller and have more gain for its size.