METHOD FOR BOREHOLE TELEVIEWER ANALOG INTERFACE FOR VIDEO CASSETTE RECORDERS

摘要

DP 50 6-1211A A method for interfacing a borehole televiewer with a video cassette recorder which includes providing acoustic information from the ultrasonic logging apparatus of a borehole televiewer and defeating the automatic gain control of a video cassette recorder by superimposing a negative going short duration electrical pulse on the horizontal synchronizing pulse. Also disclosed is a method for synchronizing the VCR with a borehole televiewer system by providing an external input to the vertical synchronizing signal of a fundamental frequency and a horizontal synchronizing signal in phase and which is a harmonic of the vertical synchronizing signal.