The two oscillator circuits underneath are suitable for working with crystal oscillators in series or parallel method: Large-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 an excellent aspect of more substantial than a million and a ... https://www.hxcrystals.com/seokeywords/bulk-crystal-oscillator.html