A nuclear frequency-modulation spectrometer (NFMS) for high-resolution gamma-ray spectroscopy is described in this article. As the name implies, this device operates by modulating the cross section for gamma-ray absorption. The automation of this spectrometer required the development of an interface to an Apple computer which provides a real-time data display. This interface also enables the Apple computer to control up to two Mossbauer spectrometers at once, with a real-time data display for each. A nuclear frequency-modulation spectrometer makes it possible to observe directly the phenomenon known as Hrf sidebands" in M6ssbauer spectroscopy,without interference from the "parent transitions." The high resolution of NFMS makes it possible to examine the "rf sidebands" for any fine structure.