DEVICE FOR PROTECTING SCREEN INTERFERENCE ON PLAYBACK OF PAL PLUS TAPE FOR PAL TYPED VTR

摘要

The present invention relates to a device for preventing interference signals during playback of a Palm Plus tape. In particular, a tape recorded in a Palm Plus system is generated on a screen when playing back with a general Arm system VTR instead of a Palm Plus VTR. The present invention relates to an apparatus for preventing interference during playback of a Palmerstape playback in an arm type VTR for preventing an interference signal.;A screen for preventing interference caused by a helper signal inserted during a certain horizontal scanning period when playing a Palm Plus tape recorded in a Arm Plus method in an arm type VTR, wherein the arm tape and arm plus A tape selection switch unit for selecting a tape; Microcomputer control unit that controls the output level according to the presence or absence of helper signal by incorporating the compound synchronous signal: A mono-multi which outputs only the video signal part at high level except synchronous and burst signal in the horizontal scanning period. part; A gate unit for injecting the output signal of the tape selection switch unit, the microcomputer control unit, and the mono-multi unit into an end logic; And a video signal muting control unit which mutes the video signal when the helper signal is inserted into the horizontal scan line by introducing the output of the gate unit. In the present invention described above, when a Palmerstape recorded with an Armplus-only VTR is played back in a general arm system VTR and viewed on an arm-type TV, the upper and lower ends of the horizontal scan area where the helper signal is inserted are treated as a black screen and helper signals. Provided is an apparatus that can normally watch TV without interference.