Справочник Пользователя для Triax DVB 63S

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T E C H N I C A L   T E R M S
Aerial cable:
Connecting cable between the modula-
tor of the satellite receiver and the aerial
input of the tv, as an alternative if there
is no SCART-socket.
AV: see SCART
Coaxial cable:
Connecting cable between LNB and
satellite receiver, for the transmission of
signals received and power supply of
the LNB.
Data compression/MPEG1/MPEG2
For the transmission of the present tv-
standard (625 lines and 50 Hz image
replication frequency)  there is a digital
data quantity of 216 Mbit/s. This would
require band widths which are not avail-
able, neither terrestrially nor for satel-
lites. Therefore a reduction of the data
quantity is made through data reduc-
tion. In Europe MPEG-2  has been de-
termined as a universal standard of
data compression. MPEG2 is an exten-
sion of MPEG1.
Deemphasis:
Adaptation of the audio frequencies to
the transmitter signal, determined by
the transmission parameters of the sat-
ellite.
DiSEqC
Digital Satellite Equipment Control: A
digitalt control signal for the control of
the DiSEqC-compatible components of
the ODU via the coaxial cable.
DVB
Digital Video Broadcastning: a digital,
universal transmission technique for
picture, graphics, sound and text. Also
for all kinds of data and in any possible
and suitable quality.
Frequency:
Physical quantity, states number of os-
cillations per second, measured in
Hertz (Hz).
Frequency range:
a)
Satellite and LNB, respectively:
11 GHz range from 10,70 GHz to 11,70
GHz
12 GHz range from 11,70 to 12,75 GHz
b)
Receiver: IF or 1.MF 950 to 2150
MHz
Frequency unit / Description / Oscilla-
tions per second
1 Hz
1 Hertz
1
1 kHz
1 Kilohertz
1.000 Hz
1 MHz 1 Megahertz 1.000.000 Hz
1 GHz 1 Gigahertz 1.000.000.000 Hz
Intermediate Frequency (IF):
The frequency range radiated from the
satellite cannot be transmitted through
a cable and is therefore converted by
the LNB in the IF range from 950 to
2150 MHz. In this way transmission and
processing in the receiver is made pos-
sible.
1. IF = Intermediate frequency.
LNB/LNC (Low Noise Blockconverter):
Receiver unit in the focal point of the
dish, converts the frequency range of
the satellite to the IF of the receiver.
LOF:
Local oscillator frequency, statement in
MHz or GHz, depending on LNB and
frequency range received.
Reception frequency of the receiver =
the transmitter frenquency of the satel-
lite - LOF.
Modulation with 22 KHz
For universal LNB to switch to high fre-
quency range.