The 2 oscillator circuits under are suitable for employing crystal oscillators in series or parallel method: Higher-repetition-amount and high-electricity picosecond regenerative amplifier dependant on just one bulk Nd:GdVO4 crystal A timing reference incorporating one-crystal-silicon micromechanical resonator with a quality element of much larger than a million along with a resonant https://www.hxcrystals.com/seokeywords/bulk-crystal-oscillator.html