Tektronix 434, Инструкция по эксплуатации

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Maintenance—434
o f the T e k tro n ix Part N um ber using the resistor color-code
system (e.g., a diode color-coded p in k or blue-brow n-gray-
green indicates T e k tro n ix Part N um ber 152-0185-00). The
cathode and anode ends o f a metal-encased diode can be
id e n tifie d by the diode sym bol marked on the b o d y. See
Fig. 4-3.
Semiconductor Lead Configuration. Fig, 4-4 shows the
lead c o n fig u ra tio n s o f the sem iconductors used in this
in stru m e n t. T his view is as seen fro m the b o tto m o f the
device.
Troubleshooting Equipm ent
The fo llo w in g e q u ipm e n t is useful fo r tro u b le sh o o tin g
the 434.
Fig . 4-3. D io d e p o la r ity m a rkin g s.
1. Transistor Tester
D escription: T e k tro n ix T yp e 576 Transistor-Curve Trace
o r equivalent.
Purpose: T o test sem iconductors used in th is in s tru ­
m ent.
2. M u ltim e te r
D escription: V T V M , 10 megohm in p u t impedance and 0
to 500 volts range; ohm m eter, 0 to 50 megohms.
A ccuracy, w ith in 3%. Test probes m ust be insulated to
prevent accidental shorting.
Purpose: T o check voltages and fo r general tro u b le ­
shooting in this in stru m e n t.
N O T E
A 2 0 ,0 0 0 o h m s /v o tt VO M can be used to check the
voltages in this in s tru m e n t i f allowances are made fo r
the c irc u it loading o f the VO M a t high-im pedance
p o in ts .
3. Test Oscilloscope
D e scrip tio n : DC to 25 M Hz frequency response, one
m illiv o lt to five v o lts /d iv is io n d e fle c tio n fa c to r. A 10X
probe should be used to reduce c irc u it loading.
Purpose: T o check w aveform s in this in stru m e n t.
4. Isolation T ransform er
D escription: P rim ary to secondary ra tio o f 1 :1 ; capable
o f supplying operating pow er fo r th is in stru m e n t.
Purpose: T o isolate pow er in p u t o f this in stru m e n t fro m
ground to allow grounding p o in ts in the internal power
supply fo r tro u b le sh o o tin g purposes.
Troubleshooting Techniques
T his tro u b le sh o o tin g procedure is arranged in an order
w h ich checks the sim ple tro u b le possibilities before p ro ­
ceeding w ith extensive tro u b le sh o o tin g . The firs t fe w
checks assure proper co n n e ctio n , operation and ca lib ra tio n .
If the tro u b le is n o t located by these checks, the rem aining
steps aid in locating the defective co m ponent. When the
defective c o m p o n e n t is located, it should be replaced
f o l l o w i n g th e re p la c e m e n t procedures given under
C orrective Maintenance.
4-4