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An introduction to the technology

Field Reactors are active bidirectional transducers. A transducer is any device which converts energy from one type to another. Examples include microphones, loudspeakers, motors and generators. A bidirectional transducer is one which has two modes of operation which are symmetrical in time. For instance, a moving coil microphone will work as a speaker when driven with an audio signal. A moving coil speaker will produce a current when the cone is made to move by a force. The chief difference between the starter motor and the alternator of a car is the speed at which their rotors turn; in terms of the general arrangement of their parts they are similar. An active transducer is one which requires a power supply.


Field Reactors sit in the family of "crossed field" devices somewhere between cavity magnetrons and the betatrons but to generate a force they exploit the same physical principles as many other electric motors where an electric current in a coil on the rotor creates a magnetic field which exerts a force on a magnetic field from the housing, the stator, which causes the rotor to move relative to the stator. An electric motor can only work because the rotor is free to move relative to the stator.


In a Field Reactor the field coil of the rotor is replaced with a space charge, a cloud of electrons, accelerated in a cavity to form a vortex circulating around the axis of the device. Because this space charge vortex and the housing are not mechanically attached they are free to move relative to each other and the magnetic field generated by the motion of the space charge exerts a force on a magnetic field from the stator, just as in other electric motors, but the arrangement of the parts causes this force to act along the axis rather than around it. The vortex-like flow of the electrons works just like the a current flowing in a coil and the whole device works like a coil next to a bar magnet, obeying Ampere's circuital law, Faraday's law and Lenz's law: when the Field Reactor is working as a thruster the space charge vortex acts as a current in a solenoid (or coil) and when it is working as a damper it works like the school experiment where a magnet is dropped down a copper pipe and takes longer to emerge from the bottom of the pipe than a non-magnetic object. Relative motion of the magnet and the space charge in the cavity induces eddy currents in the space charge which produce corresponding magnetic fields which cause a force to act which always counters the change being made to the system, resisting the external force and producing electromagnetic waves and a current. Lenz's law acts here like Newton's third law, the law of conservation of energy and momentum. 


Newton’s second law states that a force is equal to a rate of change of momentum. The momentum of electrons flowing in the field coil of the rotor of a motor or generator is transferred to whatever the motor is driving or from whatever is driving the rotor of the generator. In fact it is the electromagnetic momentum of the moving charge of the electrons, which is equal to the magnetic field made by the current in the coil, which is responsible for the force between the stator and the rotor. Please visit the Downloads page to download in pdf format a complete description of how Field Reactors work.

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