Tektronix DM505 Instruction Manual page 47

Section 5-OM 505
MAINTENANCE
There are no special preventive maintenance proced-
ures that apply to the DM 505. Refer to the power module
instruction manual for general preventive maintenance
procedures and instructions.
Tektronix, Inc. provides complete instrument repair
and calibration at local Field Service Centers and at the
Factory Service Center. Contact your local Tektronix Field
Office or representative
for
further information.
Recali bration
To ensure accurate measurements, check the calibra-
tion of this instrument after each f
000
hours of operation
or every six months i f used infrequently. In addition,
replacement of components may necessitate recali bration
of the affected circuits. Complete adjustment instructions
are given in the Calibration section.
Obtaining Replacement Parts
Most electrical and mechanical parts can be ordered
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, I nc., please check the
electrical parts list for the proper value, rating, tolerance,
and description.
Ordering Parts. When ordering replacement partsf rom
Tektronix, Inc., it is important that all
of
the rollowing
i nforrnation be included to ensure receiving the proper
parts.
1, lnstrument type (include modification or option
numbers).
2. Instrument serial numbc
3. A description of the part (i lectrical, indude circuit
number).
4. Tektronix part number
Heat Sink
Removal
and Replacement
Use a screwdriver or
other suitable tool to spread the
spring tabs holding UIM1 in the heat sink. Use care not to
spring the tabs beyond their elastic limit. Remove the
regulator. Reverse
this
procedure to install the heat sink.
After replacing the heat sink, make certain the heat sink
firmly grips U t021, to ensure adequate heat dissipation.
Troubleshooting Aids
Troubleshooting Charts. As an aid in locating problem
areas, troubleshooting charts are provided for the
DM 505. These charts are located in the foldout pages in
the
Diagrams and Illustrations section.
Diagrams. Complete circuit diagrams are located in the
foldout pages in the Diagrams and Illustrations section.
The portions of the circuit mounted on circuit boards are
enclosed
by
a solid line. The circuit number of each
component in this instrument is shown on a diagram. See
the first page of the Diagrams and Illustrations section
f
or
definitions of the symbols and reference designators used
on the diagrams.
Circuit Board Illustrations. I n conjunction with each
circuit diagram is
a
circuit board illustration. Each compe
nent shown on a diagram is also identified on the circuit
board illustration by its circuit number. Atable is provided
with each diagram listing components by circuit number.
The table also lists the component grid locations on both
the diagram and circuit board illustrations.
Adjustment Locations Illustration. To aid in locating
test points and adjustable components, the adjustment
locations pullout page (normally used with the Adjust-
ment procedure) permit rapid location of test points and
adjustments.
Troubleshooting Equipment. Before using any test
equipment to make measurements on staticsensitive
components or assemblies, be certain that any voltage or
current sup flied by the test equipment does not exceed
the limits of the component to be tested.