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Price: $11.99
Professional Equipment for Serious Research Applications Generation of high power micro wave using virtual cathode oscillator devices Lightning testing on cables and insulators at 1.2/50 microsec and 8/20 microsec Material and dielectric testing Breaking of raw diamonds in mineralogy High voltage and magnetic pulser High repetition rate high power CO2 lasers Generating EMP on parallel plate transmission lines Bridge wire exploding Electron injection into nuclear reactors Electron accelerators Kilo amp linear accelerators Current injection and generation Radiation generator for high voltage steep pulser Flash x-ray generation Pulsed electron generation Short duration luminous flash for ultra high speed photography Firing boxes for pyrotechnic substance reliability testing Exploding unattended munitions Nuclear electromagnetic pulse generator Generation of plasma focusing Generation of axial plasma for injection purposes Remote de-programming of processors used in computers and other control circuitry Educational demonstration of electrical pyrotechnics, etc.. The Marx impulse generator can simulate a lightning strike. As an example most lightning discharges are in the order 1 to 100 kilo-amps with 500 kilo-amps a rarity. The electric charge associated is usually 5 to 50 Coulombs. At a voltage of 50 to 500 million volts this transforms to a considerable amount of discharged energy. The rise time of the discharge is usually 1 to 10 microseconds with a fall time of 20 to 50 microseconds. Even though this equates out to a destructive event the current rise is not as fast as the man made impulse generator. In other words Mother Nature got us in joules but not in nanoseconds!!! The reason for the relatively slow rise is due to the atmosphere not approaching an ideal spark gap switch. The output of the Marx is under 100 kilo-amps but its current rise is faster than a natural lightning bolt. Materials testing such as cables transformers and power systems can be verified for integrity against lightning. Flash x-rays and the simulating of electro magnetic pulse (EMP) from nuclear detonations are possible using this device. The output can be coupled into a suitable load, parallel flat line antenna etc. For flash x-rays you must couple the output to a suitable x-ray tube. How It Works Marx generators are basically very simple in theory, a stack of capacitors is charged in a parallel configuration to a voltage "E" and then discharged in series with a voltage of "nE" where "n" in the number of capacitors charged. Sounds simple in theory but in reality several problems must be addressed. selection of the capacitors will determine the peak current and rate of current rise during the discharge cycle that are now figures of merit for the system. Not only must we select the value of capacity and voltage but now must consider the discharge loop inductance and peak current handling of this part. Needless to say this part is far more expensive than normal oil filled filter capacitors. These capacitors once charged must be discharged in a series configuration through special precisely spaced spark gap switches for each capacitor. Open air tungsten or molybdenum electrodes with Bruce or Rogowski discharge surfaces now switch the required currents with low "jitter" Switching times are fast but can be improved in a nitrogen atmosphere or doping the electrodes with a radio-active isotope such as cesium 137 or nickel 63. The initial charging of the capacitors is best done via a controlled current source. A good approach is the use of a current limited transformer operating at line frequency or a standard high voltage transformer with a current controlled reactor in series with the primary for higher power units. The use of semiconductors usually requires special circuit precautions and shielding from the EMP generated by most of the discharges. The output of the transformer is rectified and voltage multiplied to the appropriate charging value and applied to the capacitors by high voltage resistors. Output is continuously variable with a variac. The system is triggered manually or by a +5 volt level that generates a high voltage pulse to a third trigger electrode of the bottom spark switch. This now commences where all spark switches now simultaneously fire dumping the total charge in nanoseconds. Our basic Marx generators have charging resistors. Discharge resistors can be selected by the user dependent on the desired wave shape. Standard parallel plate transmission line with a gap of 300 mm or 500 mm is available to enable the user to couple the Marx for obtaining steep field strength of 100 Kv to 400 Kv per meter. Available Systems From Our Labs All systems allow charging voltage from zero to full value with manual and +5 volt fire control. Systems are complete and require 115 or 230 vac for operation. Discharge shaping resistors are available per your requirement or use as is for fast discharge. Typical charging times/cycles is 4 to 7 events per minute with a rise time of 5 to 8ns and pulse duration of 50ns. System must not be in proximity to electronic equipment without suitable discharge shaping resistors. MARXINST1 - IU1080 Instruction Booklet
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