| 摘要 |
In an NMR diagnostic apparatus, it is generally necessary to tune a receiver tuning unit with respect to a patient. The NMR diagnostic apparatus is comprised of a standard signal generator for generating a CW signal, a receiver tuning unit which is mainly constructed by a receiver probe head and a series circuit of a capacitor and a variable capacitance diode and receives the NMR signals induced from the CW signal, quadrature detectors which detect the NMR signals, and a signal processor which processes the detected NMR signals so as to produce the control voltages "Vc". The automatic tuning operation is carried out in such a manner that varying the control voltage "Vc" which is applied to the variable capacitance diode enables the receiver tuning unit to be tuned with respect to the object that is positioned in the receiver probe head. |
