DVB:
Digital Video Broadcasting: A universal digital transmission
technology used for pictures, graphics, sound and text, i.e.
for data in any shape or form, and in any possible, always
appropriate quality.
External unit (installation):
Description applied to the entire system located outdoors,
consisting of the parabolic/offset dish as well as one or more
LNCs, used to receive signals from one or more satellites.
Frequency:
Physical measurement, indicates the number of cycles or
oscillations per second, the unit of measurement is the Hertz
(Hz).
Frequency range:
a) Satellite, respectively LNC:
11 GHz range from 10,70 GHz - 11,70 GHz, 12 GHz range
from 11,70 GHz - 12,75 GHz
b) Receiver: Intermediate frequency or 1.IF 950 to 2150 MHz
Unit Description 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
Intermediate frequency:
The range of frequencies broadcast by a satellite cannot be
transmitted via any cable. The LNC therefore converts the
signal received to an intermediate frequency range in the
band 950 to 2150 MHz. This can then be transmitted via
cable, and processed in the digital receiver.
1. IF = Intermediate frequency
LNB/LNC (Low Noise Block Converter):
Reception unit located at the focal point of the parabolic dish,
converts the frequency range of the satellite to the intermedi-
ate frequency of the digital receiver.
LOF:
Local oscillator frequency; stated in MHz or GHz; varies
depending on the LNC and the frequency range received
Reception frequency of the digital receiver = Broadcasr fre-
quency of the satellite - LOF.
Modulation at 22 KHz:
Apart from 14/28 Volt switching, this serves to switch bet-
ween 2 LNC.In Universal LNCs it is used to switch to the
High range.
Operating current:
The LNC is supplied with power via the co-axial cable. To this
end the receiver supplies an operating current of either 14 or
18 Volts.
Parabolic dish:
Surface of metal or coated synthetic material, shaped like a
parabola, receives electromagnetic waves transmitted by a
satellite and concentrates them on a focal point.
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