Tektronix PSC1125, Instruction Manual

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Maintenance
7-4
PSC 1125 Digital Television Parallel-to-Serial Converter Instruction Manual
Inspection and Cleaning
This subsection describes how to determine whether the converter needs cleaning
and how to do the cleaning. Inspection and cleaning are preventive maintenance
procedures. When done regularly, preventive maintenance may prevent converter
malfunction and enhance reliability.
Preventive maintenance consists of visually inspecting and cleaning the
converter, and using general care when operating it. How often to do mainte-
nance depends on the severity of the environment in which the converter
operates.
The cabinet helps keep dust out of the converter and is a major component of the
instrument cooling system. The cabinet should normally be in place when
operating the converter.
Inspect and clean the converter as operating conditions require. The collection of
dirt on components inside can cause them to overheat and break down. (Dirt acts
as an insulating blanket, preventing efficient heat dissipation.) Dirt also provides
an electrical conduction path that can cause an instrument failure, especially
under high-humidity conditions.
To avoid personal injury or death due to electric shock, unplug the
power cord from the line voltage source before cleaning the converter.
To prevent damaging the plastics used in the converter, do not use
chemical cleaning agents. Use a 75% isopropyl alcohol solution as a cleaner,
and rinse with deionized water. Before using any other type of cleaner, consult
your Tektronix Service Center or representative.
To prevent damaging converter components, do not use high-pressure com-
pressed air when cleaning dust from the interior of the converter. (High pressure
air can cause electrostatic discharge.) Instead, use low pressure compressed air
(about 9 psi).
Exterior Inspection.
Inspect the outside of the converter for damage, wear, and
missing parts, using Table 7–2 as a guide. If the converter appears to have been
dropped or otherwise abused, check it thoroughly to verify correct operation and
performance. Repair any defects that may cause personal injury or lead to further
damage.
General Care
Inspection and Cleaning
Procedures