Tektronix 434 User Manual

Maintenance—434
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> CAUTION <
The POWER switch m ust be turned o ff before rem ov
ing o r replacing transistors.
B. DIODES. A diode can be checked fo r an open or
shorted condition by measuring the resistance between
terminals. W ith an ohmm eter scale having an internal source
of between 800 m illivo lts and 3 volts, the resistance should
be very high in one direction and very low when the meter
leads are reversed.
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S CAUTION <
Do n o t use an ohm m eter scale that has a high internal
current. High currents may damage the diode. Do n ot
measure tunnel diodes w ith an ohm m eter; use a
dynam ic tester (such as a Tektronix Type 576
Transistor-Curve Tracer).
C. RESISTORS. Check the resistors w ith an ohmmeter.
See the Electrical Parts List fo r the tolerance of the resis
tors used in this instrum ent. Resistors norm ally do not need
to be replaced unless the measured value varies w idely from
the specified value.
D. IN DUCTORS. Check fo r open inductors by check
ing co n tinu ity w ith an ohm m eter. 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 (roll-o ff).
E. CAPACITORS. A leaky or shorted capacitor can
best be detected by checking resistance w ith an ohmm eter
on the highest scale. Do not exceed the voltage rating of the
capacitor. The resistance reading should be high after initial
charge o f the capacitor. An open capacitor can best be
detected w ith a capacitance meter or by checking whether
the capacitor passes AC signals.
9. Repair and Readjust the Circuit. If any defective
parts are located, fo llo w the replacement procedures given
in this section. Be sure to check the performance o f any
circuit th at has been repaired or that has had any electrical
components replaced.
CORRECTIVE M AINTENANCE
General
Corrective maintenance consists o f component replace
ment and instrum ent repair. Special techniques required to
replace components in this instrum ent are given here.
Obtaining Replacement Parts
Standard Parts. A ll electrical and mechanical part
replacements fo r the 434 can be obtained through your
local Tektronix Field O ffice or representative. However,
many of the standard electronic components can be
obtained locally in less tim e than is required to order them
from T e ktro nix, Inc. Before purchasing or ordering replace
ment parts, check the parts list for value, tolerance, rating
and description.
NO TE
When selecting replacement parts, it is im portan t to
remember that the physical size and shape o f a com 
ponent m ay a ffect its performance in the instrum ent,
particularly at high frequencies. AH replacement parts
should be d ire ct replacements unless i t is known that
a d iffe re n t com ponent w ill n o t adversely a ffect
instrum ent perform ance.
Special Parts. In addition to the standard electronic
components, some special components are used in the 434.
These components are manufactured or selected by Tek
tron ix, Inc. to meet specific performance requirements, or
are manufactured fo r T ektro nix, Inc. in accordance w ith
our specifications. These special components are indicated
in the Electrical Parts List by an asterisk preceding the part
number. Most of the mechanical parts used in this instru
ment have been manufactured by Tektro nix, Inc. Order all
special parts dire ctly from your local T e ktro nix Field
Office or representative.
Ordering Parts. When ordering replacement parts from
T ek tron ix, Inc., include the follow ing inform ation:
1. Instrum ent type.
2. Instrum ent serial number.
3. A description o f the part (if electrical, include circu it
number).
4. T ektro nix Part Number.
Soldering Techniques
WARNING
Disconnect the instrum ent from the pow er source
before soldering.
4-8

Tektronix 434 Specifications

General

Brand	Tektronix
Model	434
Category	Test Equipment
Language	English