Crystal VCO center frequency stabilizer

This device is designed to maintain a constant center frequency in NCER seismic voltage-control Led oscillators (VCO's). The center frequency of the current VCO design without this stabilizer can drift as much as +30 hertz from the preset center frequency. The drift can be caused by various factors including temperature, aging and change in battery voltage. The stabilizer will maintain the preset center frequency independent of the cause.