A description of the instrumental modifications and additions required for the conversion of this class of field‐swept, field‐modulated 60‐MHz NMR spectrometers is given. The rf portions are straightforward adaptations of the single‐coil sample circuit to pulsed operation. The standard instrument achieves field‐frequency stabilization through use of a NMR sideband oscillator employing a separate sample. While such a configuration is adequate for the normal mode of operation, it does not provide sufficient absolute stability for the pulsed Fourier mode of operation. The requisite stability was achieved by phase locking the sideband oscillation frequency to an external reference by forcing the radio frequency to change in accordance with the phase‐lock error signal. Both analytical and control channels are driven by this common rf source, as is the reference signal to the analytical channel synchronous detector.