Transistorized vibration measurement apparatus

Claim 1

IN TRANSISTORIZED VIBRATION ANALYZING APARATUS FOR ATTENUATING ALL SIGNALS OTHER THAN THOSE OF A PRESELECTED FREQUENCY, THE COMBINATION OF AN ELECTROMECHANICAL TRANSDUCER FOR CONVERTING MECHANICAL VIBRATION INTO A VELOCITY COORDINATED SIGNAL, A TRANSISTOR INTERGRATOR OPERATIVELY CONNECTED TO SAID TRANSDUCER FOR CONVERTING THE VELOCITY COORDINATED SIGNAL INTO A DISPLACEMENT COORDINATED SIGNAL, A FIRST COMMON COLLECTOR TRANSISTOR STAE INETERPOSED BETWEEN AND COUPLING THE TRANSDUCER AND THE INTEGRATOR, A MIXER STAGE COUPLED TO THE OUTPUT OF SAID INTEGRATOR, MIXER STAGE COUPLED TO THE OUTPUT OF SAID INTEGRTOR, MEANS INCLUDING A SECOND COMMON COLLECTOR TRANSISTOR STAGE COUPLED TO THE OUTPUT OF THE MIXER STAGE, A FILTER COLLECTOR STAGE, SAID FILTER APPARATUS BEING ADAPTED TO ATTENUATE A SELECTED FREQUENCY COMPONENT AND TO PASS AS A NEGATIVE FEEDBACK SIGNAL ALL OTHER FREQUENCY COMPONENTS, A THIRD TRANSISTOR, COMMON COLLECTOR STAGE FOR APPLYING THE OUTPUT OF SAID FILTER APPARATUS AS A NEGATIVE TRANSISTOR COMMON COLLECTOR STAGE IN MIXED IN SAID MIXER WITH THE OUTPUT OF SAID INTEGRATOR,AND MEANS FOR DERIVING AN OUTPUT SIGNAL FROM THE SECOND TRNSISTOR COMMON COLLECTOR STAGE COMPRISING THOSE COMPONENTS OF THE INTEGRATOR OUTPUT WHICH OCCUR AT THE SAID SELECTED FREQUENCY.