Promax HD Ranger +, Руководство пользователя

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December 2014
23
ANNEX 3 DiSEqC COMMANDS
A3.1 DiSEqC introduction
The DiSEqC
TM
(Digital Satellite Equipment Control) is an open protocol created
by Eutelsat in 1997 as a communication standard between satellite TV receivers
and external peripherals. The DiSEqC
TM
communications are based on the control
commands, which travel combined with power voltage through the coaxial cable
that leads the TV signal. The compatible peripherals and receivers detect these
commands and react in agreement with such.
A DiSEqC
TM
command is a digital command represented by a succession of
binary messages: “0” and “1” obtained when modulating the 22 kHz signal.
The
DiSEqC
TM
usually is used in the satellite TV facilities in order to use different
types of switchers, through the coaxial cable that leads the TV signal.
A3.2 To begin: The Universal LNB
The Universal LNB is the simplest and most used LNB. This allows the signal
reception coming from one single satellite.
TWIN (2 independent outputs), QUAD (4 independent outputs) and OCTO
(8 independent outputs) versions exist in the market. Each output is independent
from others and can be connected to a different receiver.
An universal LNB is controlled by means of a power voltage and a 22kHz signal,
sent through the RF cable, which allows us to switch between the different bands
and polarities, according to the following table:
‘ Standard ’
1 satellite only
1 receiver
‘ TWIN ’
1 satellite only
2 receivers
‘ QUAD ’
∗
1 satellite only
4 receivers
‘ OCTO ’
1 satellite only
8 receivers
Power Band Polarization(linear / circular)
13 V
18 V
13 V + 22 kHz
18 V + 22 kHz
Low
Low
High
High
Vertical / Right
Horizontal / Left
Vertical / Right
Horizontal / Left
∗
Not to confuse with LNB Quattro used in collective facilities.