Imagine Videotek LLM-1770, Инструкция по установке и эксплуатации

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Appendix C
Glossary
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SAW Filter. Surface Acoustic Wave filter
Segment Error Rate (SER). A calculated average of uncorrected transport stream packets
vs. total packets as accumulated over a designated period of time.
Sensitivity. Sensitivity is set by Consecutive Errored Samples (CES). When setting amplitude
limits, a noise spike can exceed the limit while the video amplitude can be within the limit.
With the CES set to a low number, a spike is detected and an alarm is displayed. Set the CES
to a higher number to ignore the fast spike. Each CES occurs at 37ns intervals for SD and
13.5ns for HD. Use this as a guideline to select the appropriate CES value.
Not all alarms have CES associated with them; in such cases, use the duration to increase or
decrease the general sensitivity.
Signal to Noise Ratio -Analog (SNR). A measurement of the noise level in a signal
expressed in dB (decibels) as a ratio of between the audio or video signal’s maximum
peak-to-peak signal voltage and the measured voltage of noise present when the signal is
removed. Higher SNR figures indicate that any noise introduced by system components will
not be perceived in the picture and sound output signals.
Signal to Noise Ratio-8VSB (SNR). As applies to 8VSB transmissions, this is a calculated
average power of the ideal signal divided by the actual demodulated signal power.
SMPTE. Society of Motion Picture and Television Engineers
Standard Definition Television (SDTV). This term is used to signify a digital television
system in which the quality is approximately equivalent to that of NTSC. This equivalent
quality may be achieved from pictures originated at the 4:2:2 level of ITU-R BT.601 and
subjected to processing as part of the bit rate compression. The results should be such that
when judged across a representative sample of program material, subjective equivalence
with NTSC is achieved. The displayed picture may be either the traditional 4:3 or the
wide-screen 16:9 aspect ratio.
STL. Studio Transmitter Link
Synchronous Detection. A common detection technique used in television demodulators
that removes quadrature distortion, enabling comparison of transmitter output with video
input signal.
S-Video. Also Y/C. Transmits luminance and color portions separately via multiple wires,
thus avoiding the color encoding process and resulting loss of picture quality.
Tally. A system used to light lamps and indicate usage. Most production switchers have an
internal tally system to indicate selected functions, and which selected functions are
currently involved with Program.
TCP. Transmission Control Protocol
Telecine. A device used to convert film to video; movie film is digitally sampled and
converted to video frame by frame in real-time.
TCXO. Temperature Compensated Crystal Oscillator
THD. Total Harmonic Distortion
TPL. True Peak Level