Promax Promax TV EXPLORER HD ISDB-Tb, Manual

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USER’S MANUAL. TV EXPLORER HD ISDB-T/T
B
Page 46 11/2010
5) Modulations (Only in DVB-S2)
Modulation used by carriers. It defines also the system noise immunity (QPSK and
8PSK).
6) Polarization
It affects to the signal reception in the SAT band (satellite). It allows to select the
the signal polarisation among
Vertical/Right (vertical and circular clockwise) and
Horizontal/ Left (horizontal and circular counterclockwise) or, to deactivate the
polarization (
OFF
).
7) Sat Band
Selects the High or Low frequency band for satellite channel tuning.
8) LNB Low Osc.
Sets the LNB low band local oscillator.
9) LNB High Osc.
Sets the LNB high band local oscillator.
NOTE : In the channel tuning mode the Polarization and Sat Band options cannot be
modified.
This configuration menu shows, besides the QPSK/8PSK signal parameters
selected by user, all the values automatically detected:
Roll Off Nyquist filter roll-off factor.
Pilots (Only in DVB-S2) Pilots detection in transmission.
IMPORTANT REMARK
DVB channels tuning may require an adjusting process. It is recommended to follow
next procedure:
1. From the spectrum analyser mode [13], tune the channel at its central
frequency.
2. Switch to Measurements mode [12] , measurement selection.
3. If in the lower line of the screen does not appear MPEG-2 message (and
consequently BER is unacceptable), by turning the rotary selector deviate the
tuning frequency until
MPEG-2 message appears. Finally tune channel again
to minimize the frequency deviation which optimizes the BER and therefore
minimize the BER.
If it is not possible to detect any MPEG-2 channel, make sure that digital signal
parameters are correctly defined.