Tektronix 2213 - Page 89

M aintena n ce-2213 Service
C LE A
N
I N
G .
To
clean t h e i n te r io r , blow off d ust wit h
d ry, low-pressure
ai r (a p proximately 9 psi) . R emove any
remai n i
n g d ust wit h α soft br u s h or α clot h d ampene d wit
h
α solution of
mil d d etergent and water . Α cotton-ti pp ed
a pp licator is
useful for cleaning i n n a rr ow s p aces and on
ci r cuit
boar
d
s .
If t h ese met h o d s d o n ot r
emove
all
th e d u st or d irt,
t he inst r ument may b e s p ray
was hed usi ng α solutio n
of 5°/ ο mil d d etergent an d 95%
wate r
as
follows :
1 . Gai
n access to t h e p arts to be cleane d (see " R emoval
and
Replaceme n t Instructio n s") .
2 . Sp ray was h d irty pa r ts wit
h
t
h e detergent-an d -wate r
sol u tio n ; t h en use clean
water to t ho r oug h ly r inse th em .
3 .
D r y all p arts wit h low-pressure air .
S W ITC H CO N TACTS . T
h e V ertical and Ho r izontal
atte nu ators in t
h
is
instr u me n t are circuit-boa rd mou n te d
rota r y switc h es . Wh
en
cleaning
t h em, care m u st be exer-
cised to pr eserve t
h
eir
h ig h -fre que n cy ch aracteristics .
Switc h
maintenance is sel d om n ecessa r y, but if it is
re qu ire d , use
t h e followi ng clea n i ng met h od a nd observe
t h e stated pr
ecautio n .
U se o n ly h ot d eionized or
distilled wate r , 55 0 C
(131 ° F ), to clea n α rotary switc
h in
t
h
is
instrument .
Tap water contains impurities
w h ic h are left as
resi du als after evaporation .
1 . Sp ray
h ot wate r into t he slots at t he to p of each
switc
h h
ousi
ng w h ile r otati ng t h e switc h con t r ol kno b .
Sp r ay only
fo r appr oximately five secon d s, u si ng an
atomizi ng s p ray device .
2 . Dry b ot
h
t
he switc h
an
d t h e circ u it b oa rd on w h ic h
it is mounte d ,
using d ry
low-pressure
air .
3 . Ba ke t he switc h an d t
h
e ci
r
c
u it board at 75 ° C
(167 ° F ) for 15 minutes to
elimi n ate all moisture .
4 . Spray α
very small amount (only about α 1/2-seco nd
s q ui r t) of α
recommen d e d l ubr ica n t, s u c h as Νο N oise,
i n to t
he slots at the to p of t h e switc h h o u si n g .
5 . R otate
t he switc h con trol knob abo u t 180 ° an d
again s p ray α
ve r y small amou nt of l ub ricant into eac h slot .
M ost of t h e p otentiometers use d in t
h
is
instr u ment are
permanently seale d and
gene
r
ally
do
not r eq uire perio d ic
lu b rication . All switc
h
es,
bot h rotary- a nd leve r -type,
are i n stalled with pro p
e r lu b rication ap plie d w h e r e neces-
sary an d will
rarely r eq uire any a dd itio n al lu b ricatio n .
T h erefo r e, α
r
egula
r
periodic
l ub rication program fo r t h e
inst ru me n t is n ot r eco mm
ended .
S EM ICO N D U CTO R C HE C
K
S
Pe r io d ic ch ec k s
con du
cto rs in t he
T he best c
h
ec
k of
o pe r
ation in t he instrument .
LUBR ICATIO N
of t he tra n sisto rs and ot h er semi-
oscillosco pe are not r ecommen d e
d .
semicon d uctor p erfo r mance is actual
PER IODICRE AD JU ST
MEN T
To ensu re accu
r
ate
measurements, ch ec k t he p erform-
ance of t h is i n stru
m ent after every 2000 h ours of operatio n ,
or if used infre q uently, o n ce each year . In a d ditio
n , replace-
ment of com p o n ents may necessitate
rea dj ustme n t of the
affecte d circuits .
Complete Performance C h ec k and A dju stment
i n st ru c-
tio
n
s a
r e give n in Sections 4 an d 5 . T
h e Performance
C
hec k Pr ocedure can also b e
h el p ful i n localizing ce r tain
t r o ub le i n t he i nstrume
n
t . In some cases,
mino r pr ob lems
may be r eveale d or cor r ecte d b y
rea dj ustme n t . If only α
partial a
d ju stment is p erformed , see t he i
n
te r action
ch art,
Ta b le 5-1,
fo r possi b le a dj ustme n t i n te r actions
wit h ot h er
circuits .