SE7502645L

Phonograph record profile testing apparatus comprises A. A TURNTABLE SUBSTANTIALLY UNDERSIZED RELATIVE TO THE RECORD OVERALL DIAMETER FOR SUPPORTING THE RECORD WITH OPPOSITE SIDES THEREOF EXPOSED, AND B. A PAIR OF TRANSDUCERS INCLUDING SENSORS AT LOCATIONS SPACED TO RECEIVE THE TURNTABLE SUPPORTED RECORD THEREBETWEEN, TO SIMULTANEOUSLY ENGAGE OPPOSITE SIDES OF THE RECORD AND TO PRODUCE ELECTRICAL SIGNALS WHICH VARY IN RESPONSE TO MOVEMENT RELATIVE TO THE SENSORS OF RECORD SURFACE PORTIONS ENGAGED BY THE SENSORS AND GENERALLY NORMAL TO THE PLANE OF THE RECORD. The sensors may have record engagement tips at locations spaced apart along a direction which is generally normal to the plane; arm structure carries the transducers at such location; and means is provided to displace that structure to carry the tips generally radially across the record.