| Summary: | Using a solid state reaction to prepared many samples of YBa2Cu3O7−δ And (YBa2Cu3O7−δ)1−x(Ag2O)x by mixing the appropriate ratios of constituent oxides; BaO, CuO, and Y2O3 the mixture were ground to fine power and then calcined at 900 °C without Ag2O and 930 °C for using Ag2O as impurities. The calcined black power were grounded again and molded into pellets by applying a hydrostatic pressure from (0.3–0.6) Gpa. These pellets were sintered at 950 °C. Silver was added as impurities with the calcined powder with ratios of 0.3, 0.35 and 0.45 to increase its ductility. The transition temperature for the superconductor samples were done using non-contact technique. It is an easy and sensitive technique compared with four – point probe method. The maximum Tc was 110 K for YBa2Cu3O6.989. Evaporation deposition technique to deposited a thin film, of 2200 A° thickness on the surface of the samples and then annealed to room temperature. This technical reduces the resistance to 0.2 Ω and makes a good ohmic contact at liquid nitrogen boiling point (77 K) metals of various conductivity such as copper, brass aluminum and iron were used to study the effect of eddy-current loss on them and then compared with the superconducting samples, with Ag2O or without Ag2O. The maximum power loss were obtained for the superconducting samples when they cooling at liquid nitrogen temperature. The sintered pellets were drilled manually by 6 mm drill and a slot was done along its radius, to fabricate a superconducting loop antenna for receiving magnetic field signal. The best received signal was obtained when the antenna cooled to liquid nitrogen temperature.
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