Comments on "A new method for determination of the frequency spectrum of a quartz crystal and its application"

Abstract

Several issues are raised by the above-named work (ibid., vol. SW-25, pp. 24-29, January 1978) are discussed. 1) There are well-known hazards in using an oscillator as a crystal resonator test instrument. These derive from the fact that an oscillator is a self-limiting device The self-limiting oscillator produces these harmonic currents very nearly independent of the mode of resonance and generates amplitudes of distortion in the resonator which are totally undisciplined. For these reasons data taken in an oscillating circuit must beev aluated with extreme care. Some of the responses observed by Bahadur and Parshad, particularly those noted to be "nonsinusoidal," are undoubtedly the consequence of nonlinearity. Nonlinearities produce exact harmonic stresses or currents, while the resonant families of finite 3D resonators are never exactly harmonically related. 2) The oscillator circuit is originally due to Panetta (1952). 3) It is difficult to apprehend the intent of this work.