Frequency range:
a) Satellite resp. 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
Term
Oscillations p. 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 (IF):
The frequency range broadcast by a satellite cannot be transmitted via a cable connection.
The LNB thus converts the signal to an interim frequency range of 950 to 2050 MHz, which
enables the signal to be received and processed by the receiver.
1. IF = Interim Frequency,
LNB/LNC (Low Noise Block converter):
The receiving unit at the focal point of the parabolic dish antenna, it converts signals from
the frequency range of the satellite into the intermediate frequency of the receiver
LOF:
Local oscillator frequency, stated in terms of MHz or GHz, varies according to LNB as well as
according to the frequency range received.
Reception frequency of the receiver = Broadcast frequency of the satellite - LOF
Modulation at 22 KHz
This, in addition to 14/18 Volt switching, serves to switch between two LNBs. In Universal
LNBs it serves to switch to high band
Modulator
Switching mechanism in a satellite receiver or video recorder, serves to facilitate connection
via antenna cable
Mode:
determines whether a mono or stereo programme is received
Multyfeed:
External unit, consisting of one parabolic dish and several LNBs, used to receive signals
from several satellites
Parabolic dish antenna:
Dish formed in parabolic shape, made of metal or coated synthetic material, focuses the
electromagnetic waves received from a satellite in a focal point (where the LNB is mounted)
Polarisation plane:
In order to better utilize the frequency range, satellites broadcast neighbouring programmes
with opposite polarization (horizontal and vertical, or dextro-rotatory and laevo-rotatory). In
order to receive both polarisation planes one needs either two single LNBs or one V/H-LNB.
Receiver: see Satellite receiver
Satellite:
Description of satellite, usually a name in conjunction with the orbital position,
ASTRA
19° East
EUTELSAT
13° East
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