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Glossary
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S/N
Abbreviation of Signal-to-Noise
(ratio). The higher the S/N value, the
less noise and higher the picture
quality.
Search mode
A VCR operating mode used when
searching for specific scenes, by
viewing the video output or time code
values while playing back the tape at
various speeds in forward or reverse
direction.
Servo lock
Synchronizing the drum rotation
phase and tape transport phase with a
reference signal during playback and
recording so that the video heads scan
the tape in the same pattern during
playback and recording.
Standby Off mode
One of two conditions in the stop
mode. The drum does not rotate and
tape is slackened. There is no damage
to the video heads and the tape, but
the VCR is not ready for immediate
recording or playback.
Standby On mode
One of two conditions in the stop
mode. The drum is rotating and the
tape is wrapped round the drum. The
VCR is ready for recording or
playback, so a still picture can be
obtained.
Subcarrier
A sine wave imposed on the
luminance portion of a video signal
and modulated to carry color
information. Its amplitude represents
color saturation and its phase
represents hue.
Superimpose
To put a set of characters onto a
picture so that both can be seen at the
same time.
S-video
A signal format in which Y
(luminance) and C (chrominance)
signals are separated to reduce
interference between them so that
noiseless images are reproduced.
Sync signal
A reference signal consisting of
vertical and horizontal sync signals
used for synchronizing the scanning
patterns of the video camera and the
monitor.
TBC
Abbreviation of Time Base
Corrector. Electronic circuits to
electrically stabilize the playback
signals by removing color variation
and roll in the playback picture
caused by irregularity in drum
rotation and tape movement. Time
base correction reduces deterioration
of picture quality when transmitting
or copying playback signals.
Threading
See “Loading.”
Time code
Signals recorded on the tape to
supply information on tape position
such as the hour, minute, second and
frame, to assist in setting edit points
or searching for particular scenes.
Unloading
When the EJECT button is pressed,
the VCR automatically winds the
tape back into the cassette case. Also
called “Unthreading.”
User bits
Sections of time code information
consisting of a total of 32 bits that can
be used for recording information
such as date, tape ID number,
program ID number, etc.