Nautel NX50, Руководство по устранению неисправностей

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NX50 Troubleshooting Manual Reading Electrical Schematics
Page 4-2 Issue 6.0 2019-04-01
Unique symbols
Nautel uses unique symbols on electrical schematics to describe logic (two-state) signals. These
signals differ from single-state signals or analog signals that may have multiple values.
Type of inputs and outputs
On electrical schematics, names used to describe logic (two-state) input and output signals are
prefixed with a
#
symbol.
Logic level convention
The
#
prefix identifies an input or output signal that has two distinct states:
high
and
low
.
The suffix on an input or output signal name identifies the active (true) state of the signal. The
high suffix (+) indicates the more positive of the two levels used to represent the logic states.
The low suffix (-) indicates the less positive of the two levels.
Two types of logic, positive and negative, may be represented on a particular schematic. In
positive logic,
high
represents the active (true) state, and
low
represents the inactive (false) state.
In negative logic,
low
represents the active (true) state, and
high
represents the inactive (false)
state.
Identifying schematic diagrams
Each electrical schematic in this section is identified by a number that is both the figure
number and the page number. The numbers are assigned sequentially are prefixed by the letters
SD
. The electrical schematics and logic diagrams included in this section are listed in Table 4.1
on page 4-5 .