Statistical analysis of SSB phase noise test results

Statistical analysis results are reported of recent phase noise measurements on a production lot of 100 MHz to 111.25 MHz oscillators using third overtone SC-cut quartz crystals. The test results are from a lot of 262 units of 10 different frequencies. The results show the statistical variations of the close-in phase noise measurements of both the crystal and the completed oscillator. Phase noise is reviewed at 10 Hz to 40 MHz offset from the carrier and analyzed in detail at 100 Hz offset where crystal noise is critical to the noise performance of the oscillator. The final results show a significant improvement over previously reported production-run data. Measured noise readings as low as -136 dBc/Hz at 100 Hz with limited process capability greater than -140 dBc/Hz are given