Tektronix 576 - Page 79

To re p lace α ceramic termi n al stri p s, use t he followi n g
p roce d ure .
Removal .
1 . U nsol de r all com po n e n ts an d connectio n s on t he
stri p . To ai d i n re p lacing the stri p , it may be ad visable to
mar k eac h lead or d raw α s k etc h s h owing t he location of
t he com po n e n ts and con nections .
2 . Pry or pull t he d amaged stri p from t h ech assis .
3 . If t he s p acers come out with t he stri p , remove t h em
from t he stu d p i n s for use on t h e new stri p (s p ace r s s h ou l d
be re p lace d if t h ey are d amage d ) .
Re p lacement .
1 . Place t he s pace rs i n t he ch assis h oles .
2 . Carefully p ress t he studs of t he stri p into t he s p acers
un til t hey are com p letely seate d . If necessary, use α soft
mallet an d ta p lig h tly, directly over t h e stu d , to seat t he
stri p
com p letely .
T h e following two tables s h ow p erti n ent info r mation a b out
t
he
Test
F
ixtu r e Inte r face locate d on t he Ty p e 576 front
panel . T h is i n terface con sists of four con n
ectors
: J
360,
J
361, J 362 and J 363 (see t h
e
Test F ixture Connectors sc h ematic in
t he Diag r ams section) . In Table 4-11, w h ere
α pin provi d es an ou t pu t o r accepts an in p ut level, t h e entry liste d und er "t r ue"
or "false" in d icates t h e state of t he termi n al w h ic h p ro d u ces t he desire d level
. In in d icati ng logic levels, negative logic
is
use d . Ι η negative logic, α low voltage level (tr u e) activates
t
h e
'D"
V ίο
on
ω τ
T E ST F IXT URE I N T ERF
AC
E
F ig . 4-5 . Com pon e n t locat i ons and wiring color codes on 2 k V
Bridge circuit board .
3 .
If
t he
st
u
ds on
t
he new ceramic st r i p are longer t han
t h ose
on t
he
old one, cut off t he excess lengt h before t he
new
stri p is pu t in p lace .
4 . R e p lace
al
Ι compone n ts
a
nd
co
n nections
. Observe
t
he
sol d ering precautio n s given un d er Sol d e r i ng
Tec
h
niques in
t h is sectio n .
Transfor mer Replaceme n t . T he p
ower transformer a
n
d
t he collector su pp ly tra n sformer in
t
h
is i n strumen t are
war r anted for t h e life of t h e instrument
. If eit h er trans-
former becomes defective, contact
your local Te k tronix
F iel d Office or re p r esentative for
α warranty re p lacement
(see t he W arra n ty note in t he front of this
manual)
.
Be sure
to re p lace only wit h α direct r ep lacement Te
k tronix tra n s-
former .
R ecalibration After R epair
After any electrical component h as been re p laced, t he
calibration of t he associate d circuit s h ould be check ed, as
well as t he calibration of ot he r closely relate d circuits .
Since t he Power Sup p ly affects all circuits, calibratio n
of
t h e entire i nstrumen t s h ould be ch ec ked if
wor
k h
as been
d one in t he Power Su pp ly o r if t he p ower transformer h
as
been r e p lace d . T h e Performan ce C h ec k and
Calibration
P
ro-
cedure in Section 5 provi d es α mea n s of ch
ec
k
ing instru-
ment op eration a n d ma k ing n ecessary
ad j ustme n ts .
function .
Cu rr en t
Si
nk ing
Wh en terminal acce p ts
current from exte r nal
circuit .
Curre n t So urcing
Wh en terminal su pp lies
current into external
circuit .
TA BLE 4-10
M aintena n ce-Type 576
Ex p la n ation of t he te r ms Si nk an d Source
Current Si nk ing
Wh en terminal acce p ts
cu r rent from exte rn al
loa d .
Current Sou r cing
Wh en terminal su pp lies
cu r re n t into external
loa d .