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NEWSCIENCENEWSCIENCENEWSCIENCE frequency and the signal applied to the piezo. The circulating current is rich in harmonics, and this is necessary for the operation of the circuit. Although the circuit is simple, it utilises the concepts of phi, of virtual rotation, of tetrahedral geometry, piezo and trans- former theory, and electrical knowledge. It is not suggested as a beginner project as a result of the high voltages present. For engineers and technicians of experience, it may be difficult to accept that the MRA is above unity. The ramifications are enor- mous. Hopefully, it will help to build a better world. these components based upon the type of application and frequency to be applied, with the goal of minimising losses. A typical capacitor with polyethylene dielectric has a dielectric constant of 2.3 times that of air. Air has a constant of 1.0, and is the basis for comparison. Titanium dioxide, however, has a dielectric constant maximum of 170, and a corresponding power factor of only 0.0006, comparable with polyethylene, so that the dissipation of primary current in the dielectric is extreme- ly low. This is where the comparison ends, because the titanium composite ‘capacitor’ is also a piezoelectric device as well as an excellent capacitor. Heat adversely affects the power factor of most dielectric materials. Titanium zir- conate, however, contains polar molecules which rotate as thermal pressure is applied. This rotation increases the dielectric con- stant if the frequency applied is equal to or lower than the resonant frequency of the dielectric. At series resonance, the rotation of polar molecules contributes to heat; as the dielec- tric constant increases, a corresponding release of free electrons occurs as a direct result of the piezoelectric properties of the device. In application, the MRA is tuned at reso- nance for maximum power transfer, then detuned slightly for maximum power gain. This relates directly to the use of thermal pressure at resonance, and the effect that this has on continued polar rotation and the release of donor electrons. The coil or primary of the MRA is a magnetic core which, relative to the fixed capacitance of the piezo, is a tuned perme- ability device. This is often used in RF devices to attain a stable resonant frequen- cy. Magnetic materials are chosen based upon the operating characteristics of the intended application to reduce eddy cur- rents in the operating range. In these applications, the resonant fre- quency of the magnet itself is avoided, as this would ‘beat’ with the oscillating cur- rent. However, in the MRA, this is the exact effect which we want. The barium ferrite magnet resonates audibly at frequencies which are harmonics of the series resonant frequency. The effect of this in a typical audio application is called harmonic distortion and is not desir- able, but, once again, in the MRA this is what we want to occur. There is energy in the harmonics, and this energy serves both to counter eddy losses as well as to oppose primary current that a magnet is in a constant state of col- lapse. This is why magnets attract material with similar lattice structures, as they attempt to fill the energy void which creat- ed them. The ‘domains’ of the magnet are fixed after the process of magnetisation, and the only way to extract electrical ener- gy is to physically spin a coil relative to a magnet. However, it is also possible to induce virtual rotation by applying the resonant frequency of the magnet, which causes the lattices and the domains to vibrate. However, the power required to do this is greater than the energy released by the vir- tual rotation. Therefore it is necessary to increase the vibration without using exces- sive current. The piezo has a virtually inexhaustible supply of free electrons, and it releases them when it is stressed. Using the piezo in series with the primary coil will almost eliminate primary current, because it is voltage which stresses the piezo, not cur- rent. Therefore the piezo can be stressed with very little actual power, and provide the current to the primary coil which vibrates the domains of the magnet. The piezo is the catalyst for the circulat- ing current with the primary coil. The cir- culating current is additive, and this is the reason for the high potentials developed across both the piezo and the primary coil. It is at this point that resonance becomes important. You must have three octaves of separation between the magnet resonant Magnetic Resonance Amplifier: Description of Operation by Joel McClain The MRA is a series resonant LC circuit in which power gain is attainable as a result of the increase in effective impedance under certain operating conditions. When the series impedance increases, primary current is reduced. When the power avail- able from the secondary coil cither remains the same or increases as the primary circuit impedance increases, a power gain occurs. This is not possible with a series reso- nant circuit made of conventional materi- als. Even unity power transfer is consid- ered to be unattainable as a result of accu- mulated losses in the componen{s which are passive (reactive) deviccs. Materials and construction methods are chosen for Dalid gldfish 54 * NEXUS FEBRUARY - MARCH 1995