Promax US TV EXPLORER II, Руководство пользователя

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USER’S MANUAL. US TV EXPLORER II
Page 34 01/2008
First it recognizes whether the signal is an analogue channel or a digital one. If
the channel is analogue, it determines the television standard of the signal. When the
signal is digital (
ATSC , ITU-T J.83/B, DVB-C , DVB-S and DSS ), it analyses for each
modulation type QAM Annex-A / QAM Annex-B / QPSK / 8QPSK / 8-VSB all the
associated parameters such as the modulation system: carriers , symbol rate , code
rate , etc.,. and determines the value of the signals under test.
If the AUTO ID function is launched in the spectrum analyzer mode, the name of
the network will appear temporarily on screen (it also appears in the measurement
display). In case of working in the satellite band the orbital position appears as well.
Whenever the process detects new parameters for a channel or frequency will
create a new channel plan containing the detected information.
NOTE :
The icon in the upper corner of a digital measurement screen states
that the signal level is higher than the minimum threshold (see the
PREFERENCES menu) but demodulator cannot lock it maybe due to
some wrong configuration parameter.
In such case, the user must press AUTO ID [25 ] key.
NOTE :
In order to identify DVB-S2 signals will be necessary to activate previously
the DVB-S2 option for digital satellite signals in the [22]
PREFERENCES menu.
5.9 Channel plans
The signal automatic identification process as much as the exploration of the
frequency spectrum could yield the generation of new customized channel plans
relative to the usual work locations of the meter equipment.
In this way the characterization of the band will be faster and easier when causing
that the equipment only analyses a shorter set of channels.