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EMPGUN1 Electromagnetic Pulse (EMP) Gun
Figure 12-1 shows the construction of a low power pulse gun that will provide kilowatts of peak power at frequencies up to 100 MHz with harmonics. The unit is shown battery powered and uses the NEON21 high voltage plasma generator plans included in this data. A higher powered more functional device is being developed in our labs and will be ready bymid 2006. This is an advanced level project requiring basic high frequency electronic skills. A spectrum analyzer can be a very valuable tool in set up Fig 12-1 but is not necessary. Expect to spend $50 to $100. All parts are readily available with specialized parts through Information Unlimited (www.amazing1.com) and are listed in Table 12-1.

Basic Theory Simplified
The ability of a signal todisrupt sensitive circuitry requires several properties. Most micro processors consist of field effect transistors (FET) operating at very low voltages. Once these voltages are exceeded, catastrophic failure becomes imminent. Forgiveness to an over voltage fault is practically non-existence due to a micro thin metal oxide between controlling elements. Any over voltage generated across theseelements consequently produces permanent damage or in some less severe cases cause de-programming. To generate these damaging voltages from an external source requires a wave that can produce a standing wave of energy across circuit board traces, components and other key points. The external signal energy therefore must be high enough for the circuitry geometry to be a significant part of energy at thewavelength. Therefore microwave having fast rise times (high Fourier equivalents) and burst duration are all figures of merit for maximizing the effect. The energy required also must be sufficient to enhance damage. A good figure of merit would be the quotient of energy/wavelength. A high power pulse of microwaves can be generated in several ways: Explosive flux compression driven virtual cathodeoscillators and their generics relatives can produce giga-watts of peak power from hundreds of kilojoules. This is where a seed current is pulsed into an inductor and at its peak being compressed by a shaped explosive charge trapping the flux creating a source of high energy. The coil must be compressed both axially and along its radius using high detonation velocity explosive such as thecyclo-trimethyltrinitramine or its derivatives PETN, or other equivalent energetic explosive. This trapped flux now produces an energy gain that is conditioned into the final peak powered pulse of microwave power (HEPM) Flux compression like that of a nuclear initiation requires precise timing of the explosive chargers. Krytron switches or similar can be used for

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flux compression instead of the more radiation hardened Sprytrons used in nuclear initiations where ionizing radiation is produced from the inherent fissionable materials. A virtual cathode oscillator can also easily be energized form a small Marx impulse generator generating 200 to 400 kilo-volts. The fast current rise and high peak power can produce apowerful burst of microwaves. Other methods are exploding wires where energy is allowed to flow into a LCR circuit and then rapidly disrupted by the explosion of the feed wire as it vaporizes at near the peak injection current. A very fast and energetic pulse is produced capable of generating an EMP pulse. Micro wave pulses are excellent candidates for damaging sensitive electronic circuitry, but muchlower frequencies are better to disrupt power grids and other similar sized systems as now the lengths of the conductive elements are more conducive to generate the high standing voltage waves. Obviously more energy is now required as breakers, switches, transformers require more energetic pulses

Circuit Description
Our circuit as shown in Figure 12 -2 provides a simple demonstration...