MECHANISMS OF HEAD-CLOGGING BY PARTICULATE MAGNETIC TAPES IN HELICAL SCAN VIDEO TAPE-RECORDERS

The head-clogging processes of video heads by particulate magnetic tap es in helical scan video tape recorders were investigated by continuou s microscopic observations of the rotating video heads using a strobos cope. It was found that most wear debris of typical tapes is expelled out of the rubbing surface of a video head and piles up on non-contact area of the exit side of the head. The wear debris which forms an agg lomerate contacts a tape surface, and is deposited on the tape surface . The following head picks it up on the rubbing surface (contact area) where the magnetic gap is located. A spacing loss occurs with a conse quential decrease in reproduced voltage.