| 摘要 |
PURPOSE:To perform accurate spectrum analysis by detecting a nuclear magnetic resonance (MNR) signal shifted from an observation range, by comparing a resonance signal passing through a low pass filter and a resonance signal not passing through said low pass filter. CONSTITUTION:The high frequency having the resonance frequency of the observation nucleus generated from a high frequency oscillator 4 is sent to a specimen coil 3 in a pulsated state through a gate 5 and allowed to irradiate a specimen 2 as a high frequency pulse magnetic field. A resonance signal is sent to a demodulator through a gate 6. The resonance signal passed through a low pass filter 10 and the resonance signal prior to passing said filter are sent to a differential amplifier 11 and the output thereof is sent to a LED display device and a computer 9. When the cut-off frequency of the low pass filter is improper, the difference signal thereof appears in the output of the differential amplifier 11 on the basis of the presence and absence of a peak frequency component to be displayed on a LED display device 12 and it is made clear that the setting of cut-off frequency is improper. |
