Tektronix 5110, Инструкция по эксплуатации

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Maintenance-5110
TRANSISTORS. The best check of transistor operation
is actual performance under operating conditions. A
transistor can be most effectively checked by substituting
a new component or one that has been checked previous­
ly. However, be sure that circuit conditions are not such
that a replacement transistor might also be damaged. If
substitute transistors are not available, use a dynamic
tester. Static-type testers are not recommended, since
they do not check operation under simulated operating
conditions.
INTEGRATED CIRCUITS. IC ’s can be checked with a
voltmeter, test oscilloscope, or by direct substitution. A
good understanding of circuit operation is desirable when
troubleshooting circuits using IC’s. Use care when check­
ing voltages and waveforms around the IC’s so that
adjacent leads are not shorted together. A convenient
means of clipping a test probe to the 14- and 16-pin IC’s is
with an IC test clip. This device also serves as an extraction
tool.
8. Repair and Adjustment. If any defective parts are
located, follow the replacement procedures given in
Corrective Maintenance. Be sure to check the perfor­
mance of any circuit that has been repaired or had any
electrical components replaced.
CORRECTIVE
MAINTENANCE
Corrective maintenance consists of component
replacement and instrument repair. Special techniques
required to replace components in this instrument are
given here.
Do not use an ohmmeter scale that has
a
high
internal current. High currents may damage the
diode.
DIODES. A diode can be checked for an open or
shorted condition by measuring the resistance between
terminals with an ohmmeter scale having a low internal
source current, such as the R X 1K scale. The resistance
should be very high in one direction and very low when the
meter leads are reversed.
RESISTORS. Check resistors with an ohmmeter. See
the Replaceable Electrical Parts list for the tolerance of the
resistors used In this instrument. Resistors normally do
not need to be replaced unless the measured value varies
widely from that specified.
INDUCTORS. Check for open inductors by checking
continuity with an ohmmeter. Shorted or partially shorted
inductors can usually be found by checking the waveform
response when high-frequency signals are passed
through the circuit. Partial shorting often reduces high-
frequency response.
CAPACITORS. A leaky or shorted capacitor can usual­
ly be detected by checking resistance with an ohmmeter
on the highest scale. Do not exceed the voltage rating of
the capacitor. The resistance reading should
be high after
initial charge of the capacitor. An open capacitor can best
be detected with a capacitance meter or by checking that
the capacitor passes ac signals.
OBTAINING REPLACEMENT PARTS
Standard Parts
All electrical and mechanical part replacements can be
obtained through your local Tektronix Field Office or
representative. However, many of the electronic com­
ponents can be obtained locally in less time than is
required to order them from Tektronix, Inc. Before
purchasing or ordering replacement parts, check the
Replaceable Electrical Parts list in Section 6 for value,
tolerance, rating and description. To determine the
manufacturer of a part, note the number listed under Mfg.
Code in the Parts List and refer to a Cross Index Mfr. Code
Number to Manufacturer listing at the beginning of the
Parts List.
NOTE
When selecting replacement parts, it is important to
remember that the physical size and shape of a
component may affect the performance of the
instrument, particularly at high frequencies. All
replacement parts should be direct replacements
unless it is known that a different component will not
adversely affect instrument performance.
Special Parts
In addition to the standard electronic components,
some special parts are used in this instrument. These parts
are manufactured or selected by Tektronix, Inc. in accor­
dance with our specifications. Most of the mechanical
parts used in this instrument have been manufactured by
Tektronix, Inc. Order all special parts directly from your
local Tektronix Field Office or representative.
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