Glossary
Page A-10 Instruction Manual: TT1260 Standard Definition Professional Receiver/Decoder
ST.TM.E10100.1
TSDT Transport Stream Descriptor Table: A component of the MPEG-2 PSI data. This table describes which type of
Transport stream it is in (i.e. DVB, ATSC etc.). It may also contain other descriptors.
TSP Transport Stream Processor.
TVCT Terrestrial Virtual Channel Table (ATSC).
U44.45 mm (rack height standard).
UART Universal Asynchronous Receiver Transmitter: A device providing a serial interface for transmitting and
receiving data.
UHF Ultra High Frequency: A portion of the electromagnetic spectrum covering 300 MHz to 3000 MHz (3 GHz).
Upconvert The process by which the frequency of a broadcast transport stream is shifted to a higher frequency range.
Uplink The part of the communications satellite circuit that extends from the Earth to the satellite.
UPS Uninterruptable Power Supply: A method of supplying backup power when the electrical power fails or drops to
an unacceptable voltage level. Small UPS systems provide battery power for a few minutes; enough to power
down the computer in an orderly manner. This is particularly important where write back cache is used.
Write back cache is where modified data intended for the disk, is temporarily stored in RAM and can be lost in the
event of a power failure. Sophisticated systems are tied to electrical generators that can provide power for days.
UPS systems typically provide surge suppression and may provide voltage regulation.
UTC Universal Time Co-ordinate: An internationally agreed basis for timekeeping introduced in 1972 and based on
international atomic time (corresponds to Greenwich Mean Time or GMT).
VCT Virtual Channel Table (ATSC).
VHF Very High Frequency: A portion of the electromagnetic spectrum covering 30 MHz to 300 MHz.
VITC Vertical Interval Time Code.
VITS Vertical Interval Test Signal: See: ITS.
VPS Video Programming System: A German precursor to PDC
WSS Wide Screen Switching: Data used in wide-screen analogue services, which enables a receiver to select the
appropriate picture display mode.
WST World System Teletext: System B Teletext. Used in 625 line / 50 Hz television systems (ITU-R 653).
XILINX A type of programmable Integrated Circuit.
Y (Luminance) Defines the brightness of a particular point on a TV line. The only signal required for black and white pict ures.