Again, the primary advantages of P-SPXOs are: frequency synthesis from 0.67MHz to 170MHz with 1ppm resolution, short lead times with available blanks, and pin-to-pin compatibility with standard oscillator. It can be used for margin testing, building prototype equipment, and as a temporary oscillator for a fixed frequency SPXO. Now the new P-SPXO advantages include Fractional-N PLL with no frequency holes, higher accuracy (SG-8101 only) and wider operating temperature range.