| 摘要 |
PURPOSE:To make it possible to automatically set the gain of a receiver to proper gain distribution correspondingly to the intensity of a FID signal within a short time, by comparing the width of an irradiation pulse with the intensity of the FID signal and calculating the intensity at the time of the excitation of a measuring irradiation pulse. CONSTITUTION:The pulse controlled by a bus controller 1 is converted to an irradiation pulse by a transmitter 2 and an irradiation circuit of a magnet 3 and a probe 4 is irradiated with the irradiation pulse to excite a NMR signal which is, in turn, detected as a FID signal by a detection circuit and amplified and detected by an RF amplifier 5 and an IF amplifier 6 to be sent to an AD converter 10 through a QD detector 8 and BPF 9. The FID signal converted to a digital signal is stored in the data area of an auxiliary memory 12 through an interface 11 and judged. One of a plurality of FID signals is transferred to a main memory and subjected to FFT to be converted to a spectrum. These conversions or judgements are controlled by a computer 14 according to the system program stored in the memory 12. |
