The 2 oscillator circuits below are appropriate for using crystal oscillators in sequence or parallel mode: Large-repetition-amount and higher-electricity picosecond regenerative amplifier based on just one bulk Nd:GdVO4 crystal A timing reference incorporating a single-crystal-silicon micromechanical resonator with a top quality variable of bigger than one million and also a https://www.hxcrystals.com/seokeywords/bulk-crystal-oscillator.html