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English
Operating instructions
the distributed programs, i.e. with static bitrate (A) or dynamic bitrate (B). Therefore information
should be obtained beforehand, using stats that can be found in the web, alternatively (but
which may not be sufficient) the supplied bitrates must be monitored for a few minutes from
the web interface or the keypad on the station control unit.
NOTE:
The updated information about the average band (used and available) is the outcome of a
mobile average in an interval of approx. 3 minutes. This settling time if the instant band changes
(e.g. removing/inserting the input lead) is 3 minutes, however if the peak band is taken there is
no need to wait this long.
A. If channels are broadcast with static bitrate (generally channels with SD – standard definition),
they should be programmed as follows:
•
Check the modulation parameter settings: input the programs in the output mux one at a
time, and with each input read the available peak bitrate.
•
After inputting all the programs, check the available peak bitrate level (found in the Bitrate
menu on the station control unit or the web interface status menus).
IMPORTANT: pay attention that the maximum bitrate limit is not exceeded, which
changes according to the set modulation parameters on the basis of the above tables.
Should there be an overflow, the red led on the module front panel lights up and a red
alarm dot lights up, and the alarm can be viewed, and the web interface status menu can
be reset, by selecting the module in question in the home page and then in the “Output”
section click on “Reset peak” (in this case, the available peak bitrate will be zero).
This reset can also be done on the control unit after entering the module menu, go
to “Output”, select the mux in question, the “Bitrate” submenu and then “Reset peak
bitrate”.
Furthermore, one or more programs are removed beginning with the one with lowest
priority. If one or more PIDs have been added manually, they will be removed first.
IMPORTANT: to keep the module immune to bitrate peaks, leave a discreet margin after
monitoring the peaks (indicatively, at least 1 Mbit/s free for each input channel).
B. If channels are broadcast with dynamic bitrate (generally high-definition – HD – channels),
the procedure to program the output multiplex is different. Before inputting a program, an
estimate of the bitrates it will be broadcast with must be known.
Proceed as follows:
Check the modulation parameter settings; first input the program with dynamic bitrate that
should be protected from a bitrate overflow. From the menu in the station control unit or
web interface monitor the available peak bitrate level for at least 1 minute, to ensure that the
remaining available bitrate level is sufficient to enable inputting other programs. Check whether
there are any static bitrate programs in the same transponder, input the programs in the output
multiplex one at a time and each time carefully monitor the available bitrates Ensure there is a
bandwidth available that is sufficient so the modulator is immune from bitrate overflow owing
to programs being input with a dynamic bitrate (remember high definition programs broadcast
with a variable bitrate, can have broadcast peaks around 20 Mbit/s *).
* These values refer to current broadcasting conditions for SD and HD programs.
Changes could occur further to technological development.
