The FTO series of low profile YIG oscillators achieves frequency-tuning speeds approximately five (5) times faster than the older industry standard MCO series oscillators with excellent phase noise characteristics (typically -104 dBc/Hz at 10 kHz) in a low profile package. Along with enhanced tuning speed characteristics of the main coil, the FM coil bandwidth typically is greater than 3.5 MHz. This feature provides for faster frequency modulation and greater PLL bandwidths in synthesizer design applications. As an additional feature, all oscillators use a single positive 12 V supply.