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.
DVB channels tuning may require an adjusting process. It is recommended to follow
next procedure:
1.
From the spectrum analyser mode
frequency.
2.
Switch to Measurements mode
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.
5.13.5 DSS (QPSK) Digital Channel Configuration
Press the Measurements Configuration
CONFIGURATION menu and turn the rotary selector
Select the signal DSS, which uses QPSK modulation. Parameters related to QPSK
modulation are described below:
1)
Spectral Inv
If necessary, activate the Spectral inversion (On). Reception will be bad if
spectral inversion has been incorrectly selected.
2)
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).
It permits to choose between 1/2, 2/3 and 6/7.
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USER'S MANUAL TV EXPLORER
IMPORTANT REMARK
[13], tune the channel at its central
[12], measurement selection.
[17] key to access the
[1] until the SIGNAL option.
HD
ISDB-T/T
B
10/2012