A microcomputer ( ffiM PC ) based pulsed NMR spectrometer
نویسندگان
چکیده
This paper describes the design and construction of a personal computer (PC) based pulsed NMR spectrometer to measure spin-lattice relaxation times in solids. The spectrometer works at 10 MHz and produces d. pulses of amplitude 200 Vp_p' The pulse programmer provides various pulse sequences such as 180°-1"-90°and 90°-1"-180°and inter pulse intervals (1")can be computer programmed. The rise and fall times of r.f. pulses are less than 0.4 f.ls. The rejection ratio of the transmitter is better than 3 x 107• The overall gain of the receiver system is 120 dB with a band width of 2 MHz. The recovery time of the receiver is 7 f.lS.The PC controls the spectrometer and data acquisition system.A detailed description of the spectrometer is presented.
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