Figure 2-1. Tape wraps
Learning Event 2:
FUNDAMENTALS OF TAPE CONSTRUCTION AND REPAIR OF THE VIDEO TAPE
1.
Because the video signal is much more sensitive to dropout than audio, it is desirable to have a
tape designed for video recording. There is also a difference in the way tape is manufactured for helical
scan video recordings as compared with that of quadruplex recording. The oxide particles are oriented
longitudinally for helical scan video and transversely for quadruplex recording. It was found that if the
oxide material is bonded to the film base in a pattern similar to the video recording pattern, the signal-to-
noise ratio of the tape would be increased. Do not use helical scan recording tape on quadruplex
recording equipment.
2.
If it becomes necessary to repair a tape that is broken or crumpled, which requires cutting and
splicing, it is very important that the tape be spliced precisely. Theoretically, if the tape is cut at a 90-
degree angle and all tracks are aligned, the effect is vertical wipe with no roll or tear visible in the
picture. If the tape is cut at the angle at which the video signal is recorded, an instantaneous transition
from one scene to another will occur. Either method is acceptable. However, do not splice a video tape
unless there is no other way of correcting the problem.
3.
In most audio tape recorders, the tape is always wound on the reels with the oxide coating on the
inside. The video recorders may wind the tape with the oxide to the inside or outside. Audio tape may
be recorded in both directions while video tape is recorded across the entire width of the tape in only one
direction. This means that the video tape must be rewound onto the supply reel after each playing to
prepare it for replay.
Learning Event 3:
FUNDAMENTALS OF VIDEO TAPE TRACKS
1.
Normally, there are four signals recorded on the tape; two audio tracks, a video track, and control
track. The primary audio track is used to record the program audio, and the auxiliary audio track is used
for cue information
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