Corrective Maintenance; Obtaining Replacement Parts; Component Replacement - Tektronix 221 Instruction Manual

CORRECTIVE MAINTENANCE

Obtaining Replacement Parts

Standard Parts. All electrical
replacements for the 221 can be obtained through your
local Tektronix Field Office or representative. Many of the
standard electronic components, however, can be obtained
locally in less time than is required to order them from
Tektronix, Inc. Before purchasing or ordering replacement
parts, check the parts list for value, tolerance, rating and
description.
NOTE
When selecting replacement parts, remember that the
physical size and shape o f a component may affect its
performance in the instrument. A ll replacement parts
should be a direct replacement unless a different
component is known to n o t adversely affect the
instrument's performance.
Special parts. In addition to the standard electronic
components, some special components are used in the 221.
These components are manufactured
Tektronix, Inc. to meet specific requirements, or are
manufactured for T ektronix, Inc. in accordance with our
specifications. 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 representative.
Ordering Parts. When ordering replacement parts from
Tektronix, Inc., include the following inform ation:
1. Instrument type.
2. Instrument serial number.
3. A description of the part (if electrical, include circuit
number).
4. Tektronix Part Number.

Component Replacement

Disassembly. To gain access to the interior o f the
instrument, unwind both the power cord and the attached
probe cord from the rear o f the instrument. Remove the five
screws in the bottom cover of the instrument. See Fig. 7-1.
Gently separate the bottom cover from the instrument and
lay aside. The Power Supply circuit board with the batteries
(can be lifted up and pivoted out of the way. Most of the in­
ternal workings of the instrument are now accessible.
circuit board, remove the knobs from all of the external
and mechanical part
control shafts. Remove the tw o screws securing the instru­
ment side panel to the Input circuit board and remove the
instrument side panel.
or selected by
REV. APR
If it is necessary to have access to the fro n t of the Input
W A R N I N G
Disconnect the instrument from any external power
source before replacing components.
Fig. 7-1. Location of circuit boards and securing screws.
1 9 7 4
Section 7—221 Service
I
7-1