NMR FREQUENCY LOCKING CIRCUIT

摘要

An NMR locking mechanism for use with not only electromagnets. superconducti ng magnets and permanent magnets, but also with ultrahigh energy product magnets (19) such as neodynium. The circu it utilizes a single conversion superheterodyne re- ceiver (14) with a phase locked loop that forms a locking mechanism that depends upon a variable frequency (7?). The resonant frequency of the nuclei is compared to a variable excitation frequency (63) which is adjusted to maintain a control frequency, with one unique value of the control frequency being zero at lock.