Quartz crystal compensation circuit

摘要

A compensation circuit is provided for a piezo-electric quartz crystal in a filter circuit for reducing the influence of the secondary resonance frequencies of the crystal on the filter characteristic. The Q-value of the crystal at one or several secondary resonance frequencies is reduced by connecting to the crystal a two-terminal network the impedance of which has a real and an imaginary part so that the real part gives an ohmic contribution which at the resonance frequency of the imaginary part reduces the Q-value of the crystal.