Appendix D
♦
Glossary
142
CMN-41 Series Installation and Operation Handbook
Copyright © 2009, Harris Corporation
Segment Error Rate (SER)
A calculated average of uncorrected transport stream
packets vs. total packets as accumulated over a designated period of time.
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
Transport Stream-ATSC (TS)
Consists of the following: (1) Packets: 188 bytes -
fixed length with descriptive data, (2) Carries several programs, (3) has a PID which
identifies the type of TS packet (video, audio, other), and (4) carries descriptive
information about the program.
UHF
Ultra High Frequency