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CPD-1320
SAFETY CHECK-OUT
(US Model Only)
After
corre
cti
ng
th
e o
riginal
service
problem,
perform
the following
safety
che
cks
before relea
sing
the
set
to
th
e
cu
sto
m er
:
1.
C
he
ck
the
area
o
f
yo
ur
repair
for
un
soldered o
r
poo
rl
y
-soldered
connec
tions
.
Ch
e-c
k
th
e e
ntire
board
surfa
ce
for
sold er
splashes
and bridges.
2
.
Ch
e
ck
th
e interboa
rd
wiring
to
ensure
that
no
wires are "pinched"
o
r
con
la cl
high-wa ltagc
re
sistors.
3.
Ch
ec
k th at
all
co
nt
ro
l kn
obs,
shi
e
lds,
covers,
grou
nd
straps,
and
mo
unting
hard
ware
h
ave
been replaced.
Be
abso
lut
e ly
ce
rtain
th
at you
have replaced
all
th
e
insulators.
4
.
Look for
unauthorized
repla
ce
m
e
nt
part
s,
par-
ti cularly
transistors
.
t
h
at
were
ins
tall
ed
during a
previo
u
s repa
ir.
Po
int them
ou
t
to
th
e custo
mer
and
reco mme
nd
their
replace
m ent.
5.
Loo
k
fo
r
parts which
, tho
ugh fun
c
ti
o
ning,
show
obvious
sign
s of
de
teri
o
ration
.
Poi
nt
th
e
m
o
ut
to
the
cust
o
m
er a
nd re
co
mm
e
nd th
ei
r
rep
la
ce-
m
e
nt.
6
.
Ch
ec
k the
line
co
rd
fo
r cra
cks
and
abrasio
n
.
Reco
mmend
the
rep
laceme
nt
o
f an
y
su ch
line
co
rd
to
th
e
cu
stomer
.
7
.
Check the condition
o
f
the m
o nopole an
t
e
nna
(if
any).
Make sure
th
e e
nd
is
not broken
o
ff,
and
has
the plasti
c
cap
o
n
it.
Po
int
out
the danger
o
f
i111
pa
le
111enl
o
n
a
broke
n
ant
e
nna
lo
the
customer,
and
re
co
mm
e
nd
the
ant
e
nna's
re
placement.
8.
Ch
ec
k th
e
B+
and
HY
to see they are
at
the
valu
es
speci
fi ed
.
Make
su
re
your inslru
m en
ls
are
accura
te
; he
suspicio
us
o
f
yo
ur HY
meter
if
se ts
always
have low
HY
.
9
.
C heck
th
e
a
nt
e
nna
te rminals,
mel;il
trim,
"me
lalli7.ed
"
knobs,
scre ws,
and
all
o
th er
exposed m
e
tal
part
s
for 11.C
lrakage.
C
hec
k
leabge as
de
scribe
d
be
low
.
0
.
15µF
To
Exposed
Metal
Parts
on Set
1.5k
l!
Earth Ground
AC
voltme
ter
(0.75
V)
Fig.
A.
Using
an AC voltmeter
to
check AC leakage.
-3-
LEAKAGE TEST
The
11.
C lea
kage
from any exposed
metal
part to
ea
rth
ground and
fro
m
all
exposed
m
e
tal parts
to
any
exposed
me ta
l
part
having
a
return
to
chassis,
must
not
exceed
0
.5
mA
(500
microampers).
Leakage
cu rre
nt
ca
n
be
measured
by any
o
n
e of
three
me
lhod s.
1.
A
commercial
leakage
tester,
such
as
the
Simpson 229
o
r R CA WT-540A
.
Fo
llow
the
manufa cturers'
instructio
ns to use
these
instru-
ment
s.
2.
/\.
batt
ery-opera
ted AC
milliammeter.
The
Data
Precisi
o
n
245 digital
multimeter
is
su itab
le
for
t his job.
3.
Measuring
the
vo
ltage
drop
across a
re
sis
tor
by
mea ns o
f
a
YOM
o
r battery-operated 11.C
volt-
meter.
The
"
limit"
indica tio
n
is 0.
7
5
Y,
so
a
nal
og
m
e
ters
must
have
an
accura
te
low-
voltage
scale.
The Simpson
250
and
Sanwa
SH-63Trd are
exa
mples
of a
passive
YOM
that
is
suitable. Nearly
a
ll
ba
ttery
operated
digital
multime
ters
that
have a 2 Y AC range
are
sui table.
(See Fig. /\.)
HOW TO FIND A GOOD EARTH GROUND
/\.cold-water
pipe is
guaranteed
earth
grou
nd
;
the
cover-plate
retaining
screw
on
most
AC
outlet
b°c)xes
is
also at ear
th
ground
.
If
the
retaining
screw
is to
be
u sed
as
your
e
arth-ground, verify
that
it
is
at ground
by measuring
th
e resis tance
between it and a
co
ld-
water
pipe
with an ohmmeter. The reading
should be
zero o hms
.
If
a cold-water
pipe is
not
accessible,
co
nnect
a 60
-
100
watts
trouble light
(not a
neon
lamp)
between
the
h
ot side
of
the re
cep tacle a
nd the
retaining screw. Try
bo
th slots,
if ne
cessa
r
y
, l
o
locate
th
e
hot side
o
f th
e
line,
th
e la
mp sh
o
uld
light at
no
rmal
brilliance
if
the
screw
is
at
ground p
o
tential.
(Sec r:ig.
B)
Trouble L ight
Ohmmeter
:
AC Outlet
Box
-___
.1
___
.
@ I
Cold-water Pipe
Fig. B.
Checking for earth
ground.
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