The two oscillator circuits down below are appropriate for applying crystal oscillators in sequence or parallel manner: Substantial-repetition-amount and high-power picosecond regenerative amplifier based on only one bulk Nd:GdVO4 crystal A timing reference incorporating one-crystal-silicon micromechanical resonator with a quality factor of greater than one million and a resonant freq... https://nanobookmarking.com/story18874191/the-best-side-of-bulk-crystal-oscillator