Tektronix 067-0521-00, Инструкция по эксплуатации

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SECTION 4
MAINTENANCE
PREVENTIVE M AINTENANCE
Cleaning the Interior
Internal cleaning should precede calibration since the
cleaning process could alter the setting of certain calibration
controls.
One w ay to clean the interior is by vacuum a n d /o r low-
pressure compressed air (high-velocity air could damage
certain components). Hardened dirt may be removed with a
soft paint brush, cotton-tipped swab, or cloth dampened
with a water and mild detergent solution. Pay special at­
tention to high-voltage circuits where conductive dust can
cause arcing.
The contacts on the plug-in interconnecting jacks and
plugs should be lightly lubricated with an oil of the type
used on rotary-switch contacts. To extend the life of the
contacts clean and relubricate if the oil becomes contami­
nated with abrasive dust.
Visual Inspection
The instrument should be inspected occasionally for such
defects as poor connections, broken or damaged ceramic
terminal strips, improperly seated tubes or transistors, and
heat-damaged parts. The remedy for most visible defects is
obvious.
However, overheating is usually a symptom of
other unseen defects and unless the cause is determined
before parts are replaced, the damage may be repeated.
Tube and Transistor Checks
Periodic preventive maintenance checks on the tubes and
transistors used in the instrument are not recommended. The
circuits within the instrument generally provide the most
satisfactory means of checking tube or transistor performance.
Performance of the circuits is thoroughly checked during
recalibration so that substandard tubes and transistors will
usually be detected at that time.
Recalibration
To insure accurate measurements, the instrument calibra­
tion should be checked after each 500 hours of operation
or every six months if used intermittently. Complete cali­
bration instructions are contained in Section 6 of this manual.
The calibration procedure can be helpful in isolating
major troubles in the instrument. Moreover, minor troubles
not apparent during regular operation may be revealed and
corrected during calibration.
CORRECTIVE M AINTENANCE
General Information
Removal or replacement procedures for most parts in the
067-0521-00 are obvious. However, some parts require special
procedures. Removal and replacement of these parts are
discussed in the following paragraphs.
Many components in the 067-0521-00 are mounted in a
particular w ay to reduce stray inductance and capacitance.
Therefore, carefully install replacement components to dupli­
cate lead length, lead dress, and location of the original
component.
After replacing any electrical components, be sure to
check the calibration of the instrument. Components of the
same type usually exhibit slightly different characteristics
and w ill often affect calibration.
Standard Parts
Many components in the instrument are standard elec­
tronic parts available locally. However, all parts can be
obtained through your Tektronix Field Engineer or Field
Office.
Before purchasing or ordering, consult the parts
list (Section 7) to determine the value, tolerance, and rat­
ing required.
Special Parts
Some parts are manufactured or selected by Tektronix to
satisfy particular requirements, or are manufactured for Tek­
tronix to our specifications. These and most mechanical parts
should be ordered directly from your Tektronix Field Engineer
or Field Office.
See “ Parts Ordering Information" and
“ Special Notes and Symbols" on the first page of Section 7.
Soldering
Special silver-bearing solder is used to establish a bond
to the ceramic terminal strips in Tektronix instruments. This
bond may be broken by repeated use of ordinary tin-lead
solder or by execessive heating. Solder containing about
3% silver is recommended. Silver-bearing solder is usually
available locally or may be purchased in one-pound rolls
through your Tektronix Field Engineer or Field Office. Order
by part number 251-0514-00.
Soldering to Ceramic Strips:
1. Use a wedge-shaped soldering-iron tip about y 8-inch wide.
This will allow you to apply heat directly to the solder
in the terminal without touching the ceramic, thereby
reducing the amount of heat required.
2. Maintain a clean, properly tinned tip.
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