Tektronix TSG 95, Service Manual

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TSG 95 Service Manual
Diagrams and Circuit Board Illustrations
This section contains the troubleshooting procedures, block diagrams, circuit board illustrations,
component locator tables, waveform illustrations, and schematic diagrams.
Symbols
Graphic symbols and class designation letters are based on ANSI Standard Y32.2-1975. Ab-
breviations are based on ANSI Y1.1-1972.
Logic symbology is based on ANSI/IEEE Standard 91-1984 in terms of positive logic. Logic
symbols depict the logic function performed and can differ from the manufacturer’s data.
The tilde (~) preceding a signal name indicates that the signal performs its intended function
when in the low state.
Other standards used in the preparation of diagrams by Tektronix, Inc., include the following:
H
Tektronix Standard 062-2476 Symbols and Practices for Schematic Drafting
H
ANSI Y14.159-1971 Interconnection Diagrams
H
ANSI Y32.16-1975 Reference Designations for Electronic Equipment
H
MIL-HDBK-63038-1A Military Standard Technical Manual Writing Handbook
Component Values
Electrical components shown on the diagrams are in the following units unless noted other-
wise:
Capacitors: Values one or greater are in picofarads (pF).
Values less than one are in microfarads (
m
F).
Resistors: Values are in Ohms (
W
).
Graphic Items and Special Symbols Used in This Manual
Each assembly in the instrument is assigned an assembly number (for example A5). The as-
sembly number appears in the title on the diagram, in the lookup table for the schematic dia-
gram, and corresponding component locator illustration. The Replaceable Electrical Parts list
is arranged by assembly in numerical sequence; the components are listed by component
number.
Component Locator Diagrams
The schematic diagram and circuit board component location illustrations have grids marked
on them. The component lookup tables refer to these grids to help you locate a component.
The circuit board illustration appears only once; its lookup table lists the diagram number of
all diagrams on which the circuitry appears.
Some of the circuit board component location illustrations are expanded and divided into
several parts to make it easier for you to locate small components. To determine which part
of the whole locator diagram you are looking at, refer to the small locator key shown below.
The gray block, within the larger circuit board outline, shows where that part fits in the
whole locator diagram. Each part in the key is labeled with an identifying letter that appears
in the figure titles under component locator diagrams.
Locator Grid
Function Block Title
Internal Screw Adjustment
Onboard Jumper
Digital Ground
Refer to Assembly
& Diagram Number
Offboard Connector
Active Low Signal
Signal From
Another Diagram,
Same Board
Power Termination
Strap
Panel Control
Female Coaxial
Connector
Heat Sink
Decoupled Voltage
Diagram Number
Diagram Name
Component on back of board
Assembly Number
A
B
1 2 3 4
A B
D C
Section of Circuit
Board Shown