Vibration transmission function analysis - has amplitude and phase response data measurements for infra frequency input signals

摘要

The analysis of the transmission functions of various elastic support materials when subjected to signals in the infra-frequency range is based upon an oscillator input coupled to a rotary transformer. Output signals from the support to be analysed are transmitted to a buffer amplifier with built-in filter tuned to the frequency range of interest. The filtered output is passed through a differentiator circuit and a smoothing filter. Both outputs are modulated before transmission to the armature of a rotary transformer the shaft of which is coupled to the oscillator. The stator winding is coupled to an A.C. amplifier controlling a motor positioning the stator shaft of the main transformer and a second transformer. Phase measurements are made and a switching unit drives a recorder, enabling transmission characteristics to be obtained.