Philips SDV8625T/55, Руководство пользователя

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U
UHF (Ultra high frequency)
In radio or TV broadcasting: it is the frequency
range of electromagnetic waves which lies
between 300 MHz and 3 GHz (3000 MHz).
V
VHF (Very high frequency)
In radio or TV broadcasting: it is the frequency
range of electromagnetic waves which lies
between 30 MHz and 300 MHz.
6 Glossary
A
Amplifier
A device, either a single stage or a large scale
circuit with multiple stages for creating gain,
i.e. it makes small signals larger.
Antenna
A device, such as a rod or wire, which picks up
a received radio frequency signal or radiates a
transmitted RF signal.
C
Coaxial
A single copper conductor, surrounded with
a layer of insulation, covered by a surrounding
copper shield and finally, an insulating jacket.
An unbalanced transmission line with constant
impedance. In audio, this type is commonly
used for low level, line signals terminated in
RCA connectors.
F
FM (Frequency Modulation)
In radio broadcasting: a method of modulation
in which the frequency of the carrier voltage
is varied with the frequency of the modulation
voltage.
H
HDTV (High-Definition Television)
It is a digital television broadcasting system
with higher resolution than traditional
television systems (standard-definition TV,
or SDTV). HDTV is digitally broadcast;
the earliest implementations used analog
broadcasting, but today digital television
(DTV) signals are used, requiring less
bandwidth due to digital video compression.
EN
DFU_SDV8625T_55_Book.indb 32 2011-6-23 14:40:48