Triax DVB 75SI, Руководство пользователя

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TRIAX DVB 75 SI
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bandwidths that are not available either
terrestrially or via satellite.
Therefore a reduction of the data amount
is made through data reduction. In
Europe MPEG-2 is the universal
standard for data compression. MPEG2
is an extension of MPEG1.
DiSEqC:
Di gital S atellite Eq uipment C ontrol: A
digital control signal for controlling the
DiSEqC-compatible units of the dish over
the coaxial cable.
DVB:
D igital V ideo B roadcasting: a digital,
universal transmission technique for
picture, graphics, sound and text as well
as for data of any shape and quality.
Frequency:
Physical quantity, indicates the number
of cycles per second, measured in Hertz
(Hz).
Frequency range:
a) Satellite and LNB:
11 GHz range from 10.70 GHz to 11.70 GHz
12 GHz range from 11.70 GHz to 12.75 GHz
b) Receiver:
Intermediate frequency or 1 IF: 950 to 2150
MHz
Unit of frequency / Designation /
Cycles per second:
1 Hz 1 Hertz 1
1 kHz 1 Kilohertz 1,000
1 MHz 1 Megahertz 1,000,000
1 GHz 1 Gigahertz 1,000,000,000
Coaxial cable:
Connecting cable between LNB and
satellite receiver, for transmission of
signals received and for supply of power
to LNB unit.
LNB/LNC:
(Low Noise Block Converter): Receiving
unit in the dish focus, converts the
satellite frequency range to the
intermediate frequency of the receiver.
LOF:
Local oscillator frequency, indicated in
MHz or GHz, depending on LNB and
frequency range received.
Received frequency of receiver =
transmitter frequency of satellite - LOF.
Intermediate frequency:
The frequency range from the satellite
cannot be transmitted via a cable and is
therefore converted to the intermediate
frequency range from 950 to 2050 MHz
by the LNB. This allows for transmission
and processing in the receiver.
IF = Intermediate frequency
Modulation with 22 KHz:
For switching between 13/18 Volt and
between 2 LNBs. When using universal
LNB: For switching from lower to higher
range (11.70 to 12.75 GHz).
Modulator:
Output terminal on the satellite receiver
or video tape recorder, for connection to
the TV by means of aerial cable.
Multifeed:
Outdoor unit consisting of a dish and
several LNBs for reception of various
satellites.
Satellite dish:
A dish-shaped antenna (reflector) made
of metal or metallised synthetic material
for bunching of electromagnetic waves
from the satellite in a focus.
Polarisation:
For better utilisation of the available
frequency bands the satellites transmit
adjacent programmes, with opposite
polarisation (horizontal and vertical or