Tektronix 434, Инструкция по эксплуатации

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Maintenance—434
A v o id the use o f c h e m ic a l cleaning agents w h ic h
m ig h t damage the p la s tic s used in th is in s tru m e n t.
A v o id chem icals w h ic h c o n ta in benzene, to lu e n e ,
x y le n e , a cetone o r s im ila r solvents.
Exterior.
Loose d u s t accum ulated on the o u tsid e o f the
43 4 can be rem oved w ith a s o ft c lo th o r small p a in t brush.
The p a in t brush is p a rtic u la rly useful fo r dislodging d ir t on
and around the fro n t-p a n e l c o n tro ls . D irt w h ic h rem ains
can be rem oved w ith a s o ft c lo th dam pened in a m ild d e te r­
gent and w a te r s o lu tio n . Abrasive cleaners should n o t be
used.
C R T. Clean the blue p la stic lig h t filte r and the C R T face
w ith a s o ft, lin t-fre e c lo th dam pened w ith d enatured
a lco h ol o r a m ild d e te rg e n t and w a te r s o lu tio n . The
o p tio n a l C R T mesh filte r can be cleaned in th e fo llo w in g
m anner.
1. H o ld th e filte r in a ve rtic a l p o s itio n and brush lig h tly
w ith a s o ft N o. 7 w a te rc o lo r brush to rem ove lig h t coatings
o f d u st and lin t.
2. Greasy residues o r d rie d -o n d ir t can be rem oved w ith
a s o lu tio n o f w arm w a te r and a n e u tra l pH liq u id d e te rg e n t.
Use th e brush to lig h tly scrub the filte r .
3. Rinse the filte r th o ro u g h ly in clean w a te r and a llo w
to a ir d ry .
4. I f any lin t o r d ir t rem ains, use clean low-pressure air
to rem ove. D o n o t use tw eezers o r o th e r hard cleaning to o ls
on the filte r , as th e special fin is h m ay be damaged.
5. When n o t in use, store the mesh filt e r in a lin t-fre e
d u s t-p ro o f ca n ta in e r such as a plastic bag.
Interior.
D ust in the in te rio r o f th e in s tru m e n t should
be rem oved occasionally due to its e le ctrica l c o n d u c tiv ity
under h ig h -h u m id ity c o n d itio n s . T he best w ay to clean the
in te rio r is to b lo w o f f th e accum ulated d u st w ith d ry , low -
pressure air. Remove any d ir t w h ic h remains w ith a s o ft
p a in t brush o r a c lo th dam pened w ith a m ild d e tergent and
w a te r s o lu tio n . A c o tto n -tip p e d a p p lic a to r is useful fo r
cleaning in n a rro w spaces or fo r cleaning c irc u it boards.
L u b ric a tio n
The re lia b ility o f p o te n tio m e te rs , cam sw itches and
o th e r m o vin g parts can be m a in ta in e d if th e y are k e p t
p ro p e rly lu b ric a te d . L u b ric a te sw itch d etents w ith a heavier
grease (e.g., T e k tro n ix P art N o. 0 0 6 -0 2 1 9 -0 0 ). P o te n tio ­
m eters w h ic h are n o t p e rm a n e n tly sealed should be lu b r i­
cated w ith a lu b ric a n t w h ic h does n o t a ffe c t e le ctrica l
characteristics (e.g., T e k tro n ix Part No. 0 0 6 -0 2 2 0 -0 0 ). A
lu b ric a tio n k it c o n ta in in g these lu b ric a n ts and in s tru c tio n s
is available fro m T e k tro n ix , Inc. O rd e r T e k tro n ix Part No.
0 0 3 -0 3 4 2 -0 1 . T h e o n ly p o rtio n s o f a cam s w itc h th a t
re q u ire lu b ric a tio n are th e d etents and th e bushings. No
lu b ric a n t should be applied to th e cams o r co n ta cts o f a
cam s w itc h . The c o rre c t lu b ric a n t fo r the d etents and
bushings is available b y o rd e rin g T e k tro n ix P art No.
0 0 6 -1 3 5 3 -0 0 .
T ra n sistor Checks
P e rio d ic checks o f th e transistors in the 43 4 are n o t
recom m ended. The best check o f tra n s is to r pe rfo rm a n ce is
actual o p e ra tio n in the
in s tru m e n t. M ore details on
checking tra n s is to r o p e ra tio n are given u n d e r T ro u b le ­
shooting.
R ecalibration
T o assure accurate m easurem ents, check th e c a lib ra tio n
o f this in s tru m e n t a fte r each 1000 h ours o f o p e ra tio n o r
every six m o n th s if used in fre q u e n tly . In a d d itio n , replace­
m e n t o f co m p o n e n ts m ay necessitate re c a lib ra tio n o f the
a ffe cte d c irc u its . C o m p le te c a lib ra tio n in s tru c tio n s are
given in th e C a lib ra tio n section.
The c a lib ra tio n p rocedure can also be h e lp fu l in lo c a l­
izing ce rta in tro u b le s in the in s tru m e n t. In some cases,
m in o r tro u b le s m ay be revealed a n d /o r co rre cte d by
re c a lib ra tio n .
T R O U B L E S H O O T IN G
In tro d u c tio n
The fo llo w in g in fo rm a tio n is p ro vid e d to fa c ilita te
tro u b le s h o o tin g o f th e 4 3 4 . In fo rm a tio n c o n ta in e d in o th e r
sections should be used along w ith the fo llo w in g in fo rm a ­
tio n to aid in lo c a tin g the de fe ctive c o m p o n e n t. A n u n d e r­
standing o f th e c ir c u it o p e ra tio n is very h e lp fu l in lo ca tin g
tro u b le s . See the C irc u it D e s c rip tio n section fo r c o m p le te
in fo rm a tio n .
T ro u b le sh o o tin g A id s
D iagram s. C om plete c ir c u it diagram s are given on fo ld -
o u t pages in the Diagram s section. The c o m p o n e n t num b e r
and e le ctrica l value o f each c o m p o n e n t in th is in s tru m e n t
are show n on the diagram s. Im p o rta n t voltages and w ave­
fo rm s are also shown on th e diagram s. The p o rtio n s o f the
c irc u it m o u n te d on the c irc u it boards are enclosed w ith a
blue line.
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