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Modern methods of measurement allow to determinewith a high degree of axactness dieleotrics eleo'cricparameters. However, the overwhelming majority ofexisting measuring instruments made on -the basis ofthose methods are actually destructive measuring means,allowing to measure only integral characteristics ofma-berials. Modern technological process demands abasically new approach to this problems: manufacturingnew high Q and highly expensive materials(leucosapphires, artificial rubins, a number of ferritemarks, etc.) and also goods on their basis ( striplinebaz=ee5 wid microwave integral schemes, dielectricwaveguides and resonators, etc.) supposes materialscharacteristics measurements without ruining them. Fromthis point of view nondestructive methods ofmeasurement possess obvious advantages. Nevertheless,the existing non-destructive measuring means mostlyhave a not very high exactness of measurement ofdielectric permittivity, magnetic permeability andmaterial losses and also have low sensitivity to theirchanges. On the basis of our analysis, an automatedcomplex, allowing to measure samples meability withhigh degree of exactness, effectively and withoutdestruction them, has been constructed. An originalpart of the complex is a measuring devise on the basisof a waveguide junction of cylindrical and radialwaveguides. The necessary condition of natural modespresence in such a structure is out-off of alljunc±ion-forming waveguides at resonant frequencies. Insuch a case an ele6tromagnetic field of resonatingmodes appears to be concentrated in the region ofwaveguide junction and its characteristics (resonantfrequency, cl-factor ) are determined by the regionsizes and the parameters of that volume of the samplebeing tested, which is to be found in theabove-mentioned region. The coupling of a measuringresonator with the plumbing of the automatic VSWR andattenuation meter (a measuring complex block-diagram isshown in Pig. 1) is achieved by waveguide-to-coaxialadapters ending in excitation elements and a waveguidechannels selector. A test sample of flat form andarbitrary configuration in the perimeter (a substrate,a disk, etc.) is fixed on a frame with divisions on it.The frame is moved on the guides. so that the samplepart successively get into each resonant region.
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