Tektronix 434, Инструкция по эксплуатации

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Maintenance—434
3. Place the lig h t mask over th e C R T faceplate and re­
insert the C R T assembly in to th e in s tru m e n t. Be sure the
C R T faceplate seats p ro p e rly in th e f r o n t casting. The lip
on the u p p e r edge o f th e fr o n t o f the C RT shield m ust
engage th e s lo t in th e fr o n t casting.
4. Replace th e tw o screws securing th e rear o f the CRT
shield to the rear casting.
5. Seat th e C R T fir m ly against th e f r o n t casting, m aking
sure the lig h t mask is p o sitio n e d c o rre c tly . C o rre c tly align
th e C R T in th e opening in th e f r o n t casting by p o s itio n in g
and tig h te n in g the fo u r hex-head screws loosened p re ­
v io u s ly in step 1. A ls o tig h te n the th re e screws inside the
rear o f th e C R T shield. R ecom m ended tig h te n in g to rq u e
fo r the clam p screw is 4 to 7 in ch /lb s.
6. Install th e C R T so cke t on th e base o f th e C R T .
7. Install th e Z A x is C irc u it Board.
8. R econnect the d e fle c tio n pla te leads on the neck o f
th e C R T . Be ca re fu l n o t to bend or excessively squeeze the
pins.
9. R e-install th e d e la y-lin e assembly on the b o tto m o f
th e C R T shield.
10. R e-install the cover pla te on th e rear casting.
11. R e-install the C R T lig h t filte r in th e fr o n t casting.
12. Recheck in s tru m e n t c a lib ra tio n .
Fuse R eplacem ent. The o n ly fuse used in th e in s tru ­
m e n t is th e p o w e r-lin e fuse. Use o n ly a 1 1 /2 ampere
fa s t-b lo w fuse as a replacem ent.
P ow er T ra n s fo rm e r R eplacem ent. I f the p o w e r tra n s ­
fo rm e r becomes d e fe c tiv e , c o n ta c t y o u r local T e k tro n ix
F ie ld O ffic e o r representative fo r a w a rra n ty replacem ent
(see w a rra n ty note in th e f r o n t o f th is m a n u a l). Be sure to
replace o n ly w ith a d ire c t re placem ent T e k tro n ix tra n s­
fo rm e r. A fte r the tra n s fo rm e r is replaced, check th e pe r­
fo rm a n ce o f the c o m p le te in s tru m e n t.
The c o m p o n e n ts located in the p o w e r-su p p ly c o m p a rt­
m e n t can be reached fo r m aintenance b y using the fo llo w ­
ing p rocedure:
1. Remove th e w ra p -a ro u n d c a b in e t fro m th e in s tru ­
m e n t as described e a rlie r in th is section.
2. Lay the in s tru m e n t d o w n fla t w ith the p o w e r-su p p ly
c o m p a rtm e n t edge fa cin g yo u .
3. Remove the tw o screws securing th e c o m p a rtm e n t
shield to th e rear casting.
4. Loosen the tw o screws securing the c o m p a rtm e n t
shield to the fo rw a rd p o w e r-su p p ly c o m p a rtm e n t bulkhead
and slide th e shield o u t o f th e in s tru m e n t.
W A R N I N G
I
L in e A C , hig h voltage, a n d s to re d D C are p re se n t in
th is c o m p a rtm e n t. I t is re co m m e n d e d the in s tru m e n t
n o t be o p e ra te d w ith th is sh ie ld rem oved.
A fte r gaining access to the p o w e r-su p p ly c o m p a rtm e n t,
th e p o w e r tra n s fo rm e r assembly can be rem oved as fo llo w s :
1. Remove th e Power S u p p ly Secondary c irc u it board.
2. Remove the p la stic in su la tin g sheet th a t m o u n ts be­
neath th e Power S u p p ly Secondary c irc u it board.
3. Remove the m etal cover to the enclosure c o n ta in in g
th e p o w e r-su p p ly tra n s fo rm e r assembly.
4 . R e m o v e th e tr a n s fo r m e r assembly fro m the
enclosure. Be careful n o t to bend the pins.
R e calibration A fte r Repair
A fte r any electrical c o m p o n e n t has been replaced, the
c a lib ra tio n o f th a t p a rtic u la r c irc u it should be checked, as
w ell as the c a lib ra tio n o f o th e r closely related c irc u its .
Since the p o w e r supply a ffe cts all c irc u its , c a lib ra tio n o f
the e n tire in s tru m e n t should be checked if w o rk has been
done in the p o w e r supply or if the tra n s fo rm e r has been
replaced.
In s tru m e n t Repackaging
If the 43 4 is to be shipped fo r long distances by
co m m e rcia l means o f tra n s p o rta tio n , it is recom m ended
th a t the in s tru m e n t be repackaged in th e o rig in a l m anner
fo r m a x im u m p ro te c tio n . The o rig in a l shipping ca rto n can
be saved and used fo r th is purpose. T he Repackaging illu s ­
tra tio n in th e Mechanical Parts Illu s tra tio n s shows h o w to
repackage the 43 4 and gives th e p a rt num bers fo r the
repackaging co m p o n e n ts. New shipping cartons can be
o b ta in e d fro m T e k tro n ix , Inc. C o n ta c t y o u r local T e k ­
tr o n ix F ield O ffic e o r representative.
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