Tektronix 442, Инструкция по эксплуатации

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Maintenance—442 Service
Table 5-2
RELATIVE SUSCEPTIBILITY TO
STATIC DISCHARGE DAMAGE
Semiconductor Classes
Relative
Susceptibility
Level sa
MOS or CMOS microcircuits or discretes,
or linear microcircuits
with MOS inputs
(Most Sensitive)
1
ECL
2
Schottky signal diodes
3
Schottky TTL
4
High-frequency bipolar transistors
5
JFETs
6
Linear microcircuits
7
Low-power Shottky TTL 8
TTL (Least Sensitive) 9
quirements, or are manufactured for Tektronix, Inc. in
accordance with our specifications (see Cross Index-
Manufacturers Code Number to Manufacturer in the
Replaceable Electrical Parts list for code numbers). Most
of the mechanical parts used in this instrument have been
manufactured by Tektronix, Inc. Order all special parts
directly from your local Tektronix Field Office or represen­
tative.
ORDERING PARTS. When ordering replacement
parts from Tektronix, Inc., it is imperative that all of the
following information be included in order to ensure
receiving the proper parts.
1. Instrument type (include modification or option
numbers).
2. Instrument serial number.
3. A description of the part (if electrical, include the
circuit number).
a Voltage equivalent for levels:
1 = 1 0 0 to 500 V 4 = 500 V 7 = 400to 1000 V(est.)
2 = 200 to 500 V 5 = 400 to 600 V 8 = 900 V
3 = 250 V 6 = 600 to 800 V 9 = 1200 V
(Voltage discharge from a 100 pF capacitor through a resistance
of 100 ohms.)
Obtaining Replacement Parts
STANDARD PARTS. Most electrical and mechanical
parts can be obtained through your local Tektronix Field
Office or representative. However, you should be able to
obtain many of the standard electronic components from
a local commercial source in your area. Before you
purchase or order a part from a source other than
Tektronix, Inc., please check the Replaceable Electrical
Parts list for the proper value, rating, tolerance and
description.
NOTE
Physical size and shape of a component may affect
instrument performance, particularly at high fre­
quencies. Always use direct-replacement com­
ponents, unless it is known that a substitute will not
degrade instrument performance.
SPECIAL PARTS. In addition to the standard elec­
tronic components, some special components are used in
the 442. These components are manufactured or selected
by Tektronix, Inc. to meet specific performance re-
4. Tektronix part number.
Soldering Techniques
W A R N I N G
I
To prevent electrical shock or damage to the 442,
always disconnect it from the power source and
allow approximately three minutes for the filter
capacitors in the power supply to discharge before
attempting to solder in the circuitry or replace
components.
NOTE
Be sure you are familiar with soldering techniques
and parts replacement procedures before replacing
any electrical components in the 442.
Ordinary 60/40 solder and a 35- to 40-watt pencil-type
soldering iron can be used to accomplish the majority of
the soldering. If a higher wattage-rating soldering iron is
used on the etched circuit boards, excessive heat can
cause the etched circuit wiring to separate from the board
base material.
If it becomes necessary to solder in the general area of
any of the high-frequency contacts in the instrument,
clean the contacts immediately upon completion of the
soldering. Refer to the Switch Contacts paragraph in the
Preventive Maintenance part of this section for
recommended cleaners and procedures.
REV A MAY 1980 5-13