Tiernan TDR7, Руководство пользователя

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Glossary
PAL–I
A European color television transmission standard that uses
a 4.43361875 MHz subcarrier. A single frame in this standard consists
of 625 scanning line, and frames are scanned at a rate of 25 frames per
second.
PAL–M
A European color television transmission standard that uses
a 3.57561149 MHz subcarrier. A single frame is this standard consists of
525 scanning lines, and frames are scanned at a rate of 30 frames per
second.
PGCA
A proprietary conditional access method used by Tiernan
equipment that provides basic signal protection and the ability to
authorize individual IRDs.
PID
Packet Identifier—Within a data packet, the bits used for its
identification.
Pixel
Picture Element—1. The smallest unit of area of a video screen
image that can be turned on or off, or varied in intensity.
2. The smallest division that makes up the raster scan line for a video
display.
PSI
Program Specific Information.
Q
QPSK
Quadrature Phase Shift Keying—The transmission of 2 bits
per symbol, with each symbol being a phase range of the sine wave. In
this fashion, a 2:1 compression ratio is achieved, resulting in a
doubling of the efficiency with which a circuit is employed.
R
RCD
Remote Control Device—A computer terminal used to
configure and monitor an encoder or an IRD without using the unit’s
control front panel.
RF Input
The user configured receive frequency parameter.
S
Sample Rate The number of times per second that an analog signal
is measured and converted to a binary number in order to convert the
analog signal to a digital signal.