Tektronix 2246 1Y, Service Manual

Page: 173 / 433

Maintenance—2246 1Y and 2246 Mod A Service
CORRECTIVE MAINTENANCE
INTRODUCTION
Corrective maintenance consists of component
replacement and instrument repair. This part of the
manual describes special techniques and pro­
cedures that are needed to replace components in
this instrument. If it is necessary to ship your instru­
ment to a Tektronix Service Center for repair or
service, refer to the Repackaging for Shipment infor­
mation in this section.
MAINTENANCE PRECAUTIONS
To reduce the possibility of personal injury or instru­
ment damage, observe the following precautions.
1. Disconnect the instrument from the ac-power
source before removing or installing
components.
2. Verify that the line-rectifier filter capacitors are
discharged prior to performing any servicing.
3. Use care not to interconnect instrument grounds
which may be at different potentials (cross
grounding).
4. When soldering on circuit boards or small insu­
lated wires, use only a 15-watt, pencil-type
soldering iron.
f t A A A A / V W \ « 2
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CAUTION |
iv W W W V J
Do
n o t e x c e e d 9 i n - l b o f to r q u e w h e n t ig h t e n ­
in g th e 6 - 3 2 s c r e w s .
5. Use care not to overtighten screws into chassis.
Threads that have been formed directly into
aluminum components can be stripped out. If
this occurs, use a 6-32 nut to secure the screw.
^WARNIN^Jj
P o r tio n s o f th e p o w e r s u p p ly a re flo a t in g a t
th e a c lin e v o lta g e le v e l a n d p o s e a s h o c k
h a z a r d i f n o t is o la t e d fr o m g r o u n d .
6. Use an isolation transformer to supply power to
the 2246 1Y or 2246 Mod A if you troubleshoot in
power supply with power applied to the
instrument.
OBTAINING REPLACEMENT PARTS
Electrical and mechanical replacement parts can be
obtained through your local Tektronix Field Office or
representative. However, many of the standard
electronic components may usually be obtained
from a local commercial source. Before purchasing
or ordering a part from a source other than
Tektronix, Inc., please check the Replaceable
Electrical Parts list for the proper value, rating, tol­
erance, and description.
N O T E
T h e p h y s ic a l s iz e a n d s h a p e o f a c o m p o n e n t
m a y a ff e c t in s t r u m e n t p e r f o r m a n c e , p a r ­
tic u la r ly a t h ig h fr e q u e n c ie s . A lw a y s u s e
d i r e c t - r e p la c e m e n t c o m p o n e n t s , u n le s s i t is
k n o w n t h a t a s u b s t it u t e w ill n o t d e g r a d e
in s t r u m e n t p e r f o r m a n c e . P a r ts in th e c r t
h ig h - v o lt a g e a n d Z - A x is c ir c u it s a re s a f e t y -
c o n t r o lle d — U S E E X A C T R E P L A C E M E N T S in
th e s e c ir c u it s .
Special Parts
In addition to the standard electronic components,
some special parts are used in the 2246 1Y and
2246 Mod A. These components are manufactured
or selected by Tektronix, Inc. to meet specific per­
formance requirements, or are manufactured for
Tektronix, Inc. in accordance with our specifications.
The various manufacturers can be identified by
referring to the Cross Index-Manufacturer’ s Code
number to Manufacturer at the beginning of the
Replaceable Electrical Parts list (Section 8). Most of
the mechanical parts for in this instrument are
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