A spectrometer of the marginal oscillator type has been designed and constructed to operate over the range 100 to 300 Mc. The salient features of this spectrometer are that it may be frequency swept over a wide band, it is frequency modulated, and the extraneous amplitude modulation, often known as ``potato,'' is kept to a minimum and made largely independent of frequency. The spectrometer has been used with considerable success to study the nuclear resonance of Co59in various ferromagnetic environments.