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English
Operating instructions
Here the main parameters for the output mux can be set.
In particular, the first selection from the dropdown menu enables choosing the modulator
frequency: by frequency or by channel.
After which we can set: the bandwidth of the output channel, the frequency or the channel/
country, the RF level (0-15), the FEC (1/2 ,2/3, 3/4, 5/6, 7/8), the guard interval (1/4,1/8,1/16,1/32),
the constellation (QPSK,16QAM and 64QAM), the number of carriers (8K, 2K), the spectrum
(normal, inverted), the single tone, which enables using a single output tone to facilitate
measuring the output level (normal or single tone). The overflow monitor can be deactivated by
flagging or otherwise the “Overflow Alarm”.
With the single tone function active, channel input has no effect.
Standard DVB-C
For this standard, the parameters we have to set vary considerably with respect to the previous
one. Note that the bandwidth, FEC and number of carriers are not set. There are different options
for the constellation: 256QAM, 128QAM, 64QAM, 32QAM and 16QAM, and the symbol rate
has to be set. Attention, with the DVB-C standard the symbol rate determines the bandwidth,
as with 6900 MSps the mux occupies 8 MHz, with 6000 MSps it occupies 7 MHz and with 5100
MSps it occupies 6 MHz, therefore if a number of channels are involved, attention in setting the
various muxes so that they do not overlap with each other.
Should the connected user equipment have problems in locking the muxes, it is advisable to
set the spectrum in “inverted” mode.
NB: for the changes to become effective click on “Save”
