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1)
Channel BW (channel bandwidth)
Enables the channel bandwidth to be selected over a range from 1.3 MHz to
60.75 MHz. The selection of this parameter is essential for the correct operation of
the tuner, as it affects the frequency separation of the carriers.
2)
Spectral Inv
If necessary, activate the Spectral inversion (On). Reception will be bad if
spectral inversion has been incorrectly selected.
3)
Code Rate
Also known as Viterbi ratio. It defines the ratio between the number of data bits
and actual transmission bits (the difference corresponds to the control bits for error
detection and correction).
In DVB-S it permits to choose between 1/2, 2/3, 3/4, 5/6 and 7/8. In DVB-S2 it
permits to choose one of the following values: 1/4, 1/3, 2/5, 1/2, 3/5, 2/3, 3/4, 4/5,
5/6, 8/9 y 9/10.
4)
Symbol Rate
It is possible to choose over the following values: from 1000 to 45000 kbauds.
When selecting the option appears the current value, in order to modify it enter a
new value through keyboard when appears the data enter symbol appears on the
upper left corner screen.
When altering this parameter modifies automatically the value of the
Channel Bandwidth and vice versa, due to the relation that exists between these
two parameters.
Figure 21.- Mesurement configuration screen (QPSK signals).
5)
Modulations (Only in DVB-S2)
Modulation used by carriers. It defines also the system noise immunity (QPSK and
8PSK).
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USER'S MANUAL. TV EXPLORER HD
02/2010
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