Tektronix 442, Инструкция по эксплуатации

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442 S ervice
DIAGRAMS AND CIRCUIT BOARD ILLUSTRATIONS
Symbols
Graphic symbols and class designation letters are
based on ANSI Standard Y32.2-1975.
Logic symbology is based on ANSI Y32.14-1973 in
terms of positive logic. Logic symbols depict the logic
function performed and may differ from the manufac­
turer's data.
The overline on a signal name indicates that the signal
performs its intended function when it is in the low state.
Abbreviations are based on ANSI Y1.1-1972.
Other ANSI standards that are used in the preparation
of diagrams by Tektronix, Inc. are:
Y14.15, 1966 Drafting Practices.
Y14.2, 1973 Line Conventions and Lettering.
Y10.5, 1968 Letter Symbols for Quantities Used in
Electrical
Science and Electrical
Engineering.
American National Standard Institute
1430 Broadway
New York, New York 10018
Component Values
Electrical components shown on the diagrams are in
the following units unless noted otherwise:
Capacitors = Values one or greater are in picofarads (pF).
Values less than one are in microfarads
(A*F).
Resistors = Ohms (O).
The information and special symbols below may appear in this manual.
Assembly Numbers and Grid Coordinates
Each assembly in the instrument is assigned an
assembly number (e.g., A20). The assembly number
appears on the circuit board outline on the diagram, in the
title for the circuit board component location illustration,
and in the lookup table for the schematic diagram and
corresponding component locator illustration. The
Replaceable Electrical Parts list is arranged by assemblies
in numerical sequence; the components are listed by
component number *(see following illustration for
constructing a component number).
The schematic diagram and circuit board component
location illustration have grids. A lookup table with the
grid coordinates is provided for ease of locating the
component. Only the components illustrated onthefacing
diagram are listed in the lookup table. When more than
one schematic diagram is used to illustrate the circuitry on
a circuit board, the circuit board illustration may only
appear opposite the first diagram on which it was il­
lustrated; the lookup table will list the diagram number of
other diagrams that the circuitry of the circuit board
appears on.
Function Block Title
Cam Switch
Closure Chart
(Dot indicates
switch closure)
Etched Circuit Board
Outlined in Black
Refer to Waveform
Function Block
Outline
Assembly Number
Tektronix Part No.
for circuit boards
Modified Component—See
Parts List (Depicted in grey,
or with grey outline)
Strap or Link
Plug to E.C. Board
|
box
J - Identifies Panel
Controls, Connectors and
Indicators
Coaxial connectors:
male
female
Plug Index; signifies pin No. 1
External Screwdriver Adj.
Shielding
Selected value, see Parts List
and Maintenance Section for
Selection Criteria
Decoupled or Filtered
Voltage
Refer to Diagram Number
Schematic Name
and Number
REV A JUN 1980