Nautel VX150, Manual

Page: 67 / 105

VX150 TO VX2 TROUBLESHOOTING MANUAL READING ELECTRICAL SCHEMATICS
VERSION 0.1 2020-12-01 PAGE 3.3.3
Structure of Schematics
The electrical schematics are structured in a hierarchical format that is based on function and signal
flow. Wherever practical, the signal flow is from left to right. Normally, inputs originate on the left-hand
side and outputs extend to the right-hand side. Exceptions are shown by an arrow indicating the
direction of signal flow.
NOTE
: The physical location of a part or assembly was not necessarily a factor during creation of the
schematic. The full reference designation assigned to a part or assembly, in conjunction with the family
tree (see
Section 3.2, “Parts Information” on page 3.2.1 ) and the assembly detail drawings (see Section
3.4, “Mechanical Drawings” on page 3.4.1 ), will identify its location.
Figures SD-1 through SD-4 identify each major stage and its detailed interconnection. Each stage
contains cross-references that identify which blocks are the signal sources for inputs, or the destinations
for outputs.
When a sub-function is treated as a block in figures SD-1 through SD-4, its detailed circuit information
is included in its own schematic drawing(s), which is also included in this section.
Locating Schematic Diagram(s) for a Functional Block
The text inside a functional block provides the key to locating its schematic diagram(s).
1. When a functional block is assigned a reference designation (e.g.,
A2
), refer to the family trees in
Section 3.2, “Parts Information” on page 3.2.1 . Follow the family tree branches to the block that
contains the desired reference designation, and associated Nautel nomenclature (e.g.,
NAPI187
System Interface PWB
).
2. Refer to Table 3.3.1 on page 3.3.5 and use the reference designation and Nautel nomenclature to
identify the appropriate schematic diagram(s).
Example:
NAPI187 System Interface PWB
is shown on schematics SD-7 and SD-8.
3. If necessary, refer to the referenced figure in the schematics at the end of this section and locate
the next, lower-level assembly. Then, repeat this procedure until the desired schematic diagram is
found.