Tektronix 2213 - Page 208

G ENER A L N OTE S
Α . U se sc hem atic d iag
r
ams,
t he ove ra ll bl oc k
d iag r am, ci rc u it b oa rd ill ust r atio n s, and
ci
r
cu it d
esc r i p tio ns wh en a na l yzi ng l n strume n t
ma l f un ctio ns a nd
l ocati n g test poi n ts . The
sc hem atic d iag ra m s i nc l ud e ty p ica l wavefo r ms
a nd vo l tages t h at are i n te nd ed as an ai d
in t r oub l es h ooti ng .
Β . A l ways set
t he P O WER switc h to O FF a nd unp l ug
t he l i n e cord b efo re swa pp i n g, removi
n
g,
or
rep l aci n g com p onen ts, a nd b efo re co nnecti n g or
d isco nn ecti
ng lnst rume n t l ea ds and ca b l es .
C . Whe n ana l yzi
n g ci rc u it ma l f unctio n s, con si der
co nn ecto rs a nd ca
b
l
es
as
p ossi
b
l e ca u ses of
fai l u re .
S PE C I F I C N OT
E
S
WA RN I N G
T h
e
Pr
e
r egu l ato r a nd I n ve r te r ci rcu its have α
f l oati ng com mo n refe ren ce wit h r es p ect to c
h
assis
gro und . Ac-so ur ce p oten tia l is pr ese n t on the
commo
n r
efe
r
e
n
ce
p oi n ts . Co nn ect t he l nst rume n t
to t h e ac- p owe r so urce t h ro u gh an iso l atio n t r an s-
forme r to pr even t t he p ossi b i l ity of p e rson a l i n j ur y
or e qu i pme
n t
d amage
w h
e
n t r
o ub
l es h ooti ng t h ese
ci rcu its . When an au tot r an sfo r me r is a l so u se d in
t h e t ro ub l es h ooti ng p roce dur e, conn ect t he iso l atio n
tran sfo r mer to t h e ac-power sour ce, t he n conn ect
t he a u tot ran sfo r me r to t he iso l atio n t ra nsfo r me r .
F i
na
ll y, p l
ug
t h
e
l
n str
u
men
t
p owe r co rd
into the
a u tot ran sfo rm er o u t l et .