Nautel XR12, Troubleshooting Manual, Page: 211 / 283

XR12 Troubleshooting Manual Reading Electrical Schematics
Issue 3.0 2009-07-28 Page 5-3
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.
Figures
SD-1
through
SD-4
identify each major stage and its detailed interconnection. Each stage
contains cross-references that identify which block is the signal source for inputs or the destination
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, which is also included in this section.
Locating schematic diagram for a functional block
The text inside a functional block provides the key to locating its schematic diagram. When a
functional block is assigned a reference designation, refer to the family trees in
Section 3, “Parts Lists”
on page 3-1 , and follow the family tree branches to the block that contains the reference designation
and associated Nautel nomenclature (e.g., NAP34A). Refer to Table 5.1 with the Nautel
nomenclature number and the description to identify the appropriate figure number.
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, “Parts Lists” on
page 3-1 ) and the assembly detail drawings (see
Section 6, “Mechanical Drawings” on page 6-1 ), will identify its location.
Note: Schematics for some functional blocks may consist of more than one figure.