Tektronix 5110, Instruction Manual

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Mainienance-5110
PREVENTIVE MAINTENANCE
Preventive maintenance consists of cleaning, visual
inspection, lubrication, etc. Preventive maintenance per­
formed on a regular basis may prevent instrument
breakdown and will improve the reliability of the instru­
ment. The severity of the environment to which this
instrument is subjected determines the frequency of
maintenance. A convenient time to perform preventive
maintenance is preceding adjustment of the instrument.
CABINET REMOVAL
WARNING
I
Dangerous voltages exist at several points
throughout this instrument. When the instrument is
operated with the covers removed, do not touch
exposed connections or components. Some tran­
sistors have voltages present on their cases.
Disconnect power before cleaning the instrument or
replacing parts.
The cabinet sides are held in place by four latches. To
remove the cabinet sides, turn the latches 90 degrees and
pull
the sides away from the carrying handle; then, lift the
cabinet sides away from the instrument. The cabinet
bottom is held in place with four latches and four screws.
The cabinet sides protect this instrument from dust in
the interior, and also provide protection to personnel from
the operating voltages present. They also reduce the
electromagnetic radiation from this instrument or in­
terference to the display due to other equipment.
CLEANING
This instrument should be cleaned as often as
operating conditions require. Accumulation of dirt on
components acts as an insulating blanket and prevents
efficient heat dissipation which can cause overheating
and component breakdown.
Exterior
Loose dust accumulated on the front panel can be
removed with a soft cloth or small brush. Dirt that remains
can be removed with a soft cloth dampened with a mild
detergent and water solution. Abrasive cleaners should
not be used.
Interior
Dust
in the interior of the instrument should be
removed occasionally due to its electrical conductivity
under high-humidity conditions. The best way to clean the
interior is to blow off the accumulated dust with dry, low-
pressure air. Remove any dirt which remains with a soft
brush or a cloth dampened with a mild detergent and water
solution. A cotton-tipped applicator is useful for cleaning
in narrow spaces.
Switch Contacts
Switch contacts and pads are designed to operate dry
for the life of the switch. However, as the switches are not
sealed,
dust attracted to the contact area may cause
switch contacts to become electrically noisy. Cleaning
may be accomplished by flushing the contact area with
isopropyl alcohol or kelite (1 part kelite to 20 parts water).
Do not use chemical cleaning agents that leave a film or
that might damage plastic parts. Do not use cotton swabs
or similar applicators to apply cleaning agents, as they
tend to snag and leave strands of cotton on switch
contacts. Should it become necessary to remove a switch
for replacement or cleaning, refer to Component Removal
and Replacement in this section.
VISUAL INSPECTION
This instrument should be inspected occasionally for
such defects as broken connections, improperly seated
semiconductors, damaged circuit boards, and heat­
damaged parts.
The corrective procedure for most visible defects is
obvious; however, particular care must be taken if heat­
damaged components are found. Overheating usually
indicates other trouble in the instrument; therefore, it is
important that the cause of overheating be corrected to
prevent recurrence of the damage.
Avoid the use of chemical cleaning agents which
might damage the plastics used in this instrument.
Use a non-residue type of cleaner, preferably
isopropyl alcohol, total denatured ethyl alcohol, or
TP35.
LUBRICATION
Generally, there are no components in this instrument
that require a regular lubrication program during the life of
the instrument.
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