Promax CABLE RANGER, Руководство пользователя

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Chapter 4: TOOLS 49 April 2018
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Create a new Channel Plan from scratch
Figure 27.
1 Press on box "Name" to give a name to the new channel plan.
2 At the next screen, press on “Add Channel”, “Remove Channel” to edit
channel plan. When finish, press on “Save channel plan” to save changes or
“Cancel” to exit without saving.
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Description
Demodulator provides the most important measurements technicians need to
assess digital QAM channel quality. Constellation diagram is a simple and
graphical way to identify signal impairments which impact MER and ultimately
BER. An ideal QAM channel for example will be represented by a set
(constellation) of very sharp dots. These dots will become small dot clouds to
indicate the presence of noise or other signal degradation sources. In addition
to constellation diagram it also measures MER, preBER and postBER
simultaneously with the spectrum trace.
4.2 Demodulator