Describes the measuring methods which may apply specifically to characteristics of television tape machines or to recorded tapes in order to define accurately their specifications. Includes diameter of the headwheel, projection of video head pole tips, radius of curvature of the vacuum guide, longitudinal pitch of the video tracks, position of recorded vertical synchronization signal, coplanarity error of video heads, video track curvature, location of control track record along the tape, jitter of reproduced picture, velocity errors applicable to PAL and NTSC, video signal-to-noise ratio, differential gain, differential phase, moire and measuring methods applicable to other subjects.