Imagine Videotek LLM-1770, Инструкция по установке и эксплуатации

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Appendix C
Glossary
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
Category II is for measurements that occur on circuits attached to a live electrical supply
outlet (115/230 VAC).

Category III is for measurements that occur on equipment permanently connected to
the building. The distribution level equipment are usually fixed installations and circuit
breakers.

Category IV is for measurements that occur at the main electrical power supply.
IP. Internet Pro
t
ocol
IRC. Incrementally-Related Carrier
I.R.E. Refers to the Institute of Radio Engineers, and is used as a unit of measurement. In
NTSC television, 1 volt of signal equals 140 IRE units.
ISP. Internet Service Provider
Jitter. A deformation of a signal affected by poor synchronization.
Key. An effect in television where a selected portion of background video is removed and
replaced with another video.
Key Cut. In a key effect, this is the video which designates the portion of background video
which is removed.
Key Fill. In a key effect, this is the video which is used to replace the portion of background
video which was removed. This may be the same video as the Key Cut video.
Key Invert. In a key effect, this is an electronic action which reverses the polarity of the key
cut signal. It makes black appear as white, and white appear as black.
Key Mask. In a key effect, it uses a wipe pattern from the wipe pattern generator to restrict
the key cut from removing video in a portion of the screen. This requires the use of the wipe
pattern generator and the Mask/Preset Size controls.
Key Source. Another term which is the same as key cut.
Legalization. The modification of serial digital video to conform to analog color space
rules, as required by users.
LCD. Liquid Crystal Display
LED. Light-Emitting Diode
LFE. Low Frequency Effects
Lissajous. A display of the amplitude and phase relationships between two input signals.
LKFS. Loudness, K weighted, relative to nominal full scale. The LKFS unit is equivalent to a
decibel in that an increase in the level of a signal by 1 dB will cause the loudness reading to
increase by 1LKFS. A unit of LKFS is equivalent to a decibel.
If a 0 dB full-scale 1 kHz sine wave is input applied to the left, centre, or right channel input,
the indicated loudness will equal -3.01 LKFS. The weighting coefficients are different for
each channel.
LS. Left Surround