Abstract: A method of making a an NMR coil is provided. A coil is patterned of a film of a conductive material on a substrate. The coil mask is designed so that the resultant coil will have a lower resonant frequency than the desired frequency of the final coil. The coil is placed in an apparatus where it is exposed to increasing current, preferably within a magnetic field such as will be used during operation. The current is gradually increased and the coil observed for changes in its resonant frequency. When the coil is exposed to its operating current without further change in its resonant frequency, it is trimmed by removal of part of the capacitive element of the coil to the desired frequency.