Chevrolet 985203 User manual

CUSTOM SERIES
95
TRUCK RADIO 985203
This
radio
has
four
tubes
and two
hi-gain
tran-
sistors
and
is
designed
for
the
Series
95
trucks.
The
radio
consists
of a
radio
receiver
unit with
••t
••
•
~
',\
I
:I
I'
14 of
Figure
82
an
external
speaker.
This
type of
design
is
ad-
vantageous
for
both
installation
and
service
as
all
component
parts
of
the
receiver
are
readily
accessible
for
nuick efficient
replacement
when
service
is
required.
Using an
external
type
speaker
affords
the
advantage of having a
larger
type
speaker
in a
limited
space
area.
The
speak-
er
is
coupled
to
the
instrument
panel
by
a
special
'.'
Figure
83
89
type
gasket,
thereby
using
the
entire
instrument
panel
for
unusually good tone
reproduction.
ELECTRICAL DESCRIPTION
The
circuit
'
used
in
this
receiver
is
'
the
super-
heterodyne
type
that
uses
no
regeneration.
The
tuning
circuits
are
of
the
permeability
type and
are
tuned by
varying
the
iron
cores
in and out of
the
antenna,
radio
frequency and
qscillatot.
coils
like
pistons.
The '
interm
'
ediate
frequency
stages
are
tuned by
means
of two
iron
cores
in
each
transformer
and
are
adjusted
with an
insulated
screw
driver
from
the
bottom and top of
each
transformer;
both the
first
(input) and second
(output) interItlediate
frequence
transformers
are
tuned by
this
method. See
Figure
83.
The antenna
circuit
Is
capacity
'coupled to
the
antenna by
means
of an
adjustable
antenna
trim-
mer
condenser
to'
take
care
of
normal
variations
in antenna and antenna
coil
capacity. The antenna
condenser
is
adjustable
by
means
of a
small
screw
driver
and
is
located
at
the
lower
front
on
the
right
side of
the
radio
'
case.
The automatic volume
control
is
of the delayed
signal
type
and
is
very
capable of
main~aining
a
constant
level
of volume
at
all
times.
Very
high
frequency
filter
chokes
are
used
in
the
radio
frequency
grid
circuit
to
discriminate
against
ignition
interference
In
the
receiver,
thus
elim-
inating the
use
of
spark
plug and
distributor
suppressors.
TUBE
AND
TRANSISTOR COMPLEMENT
12DZ6
12AD6
12EK6
12AE6A
DS26
DS503
AND
FUNCTION '
Radio
frequency
amplifier
Oscillator
-
modulator
Intermediate
frequency
amplifier
Detector
-Automatic volume
control
and
first
audio
Audio '
driver
transistor
Audio output
"HI-POWER"
transistor
GENERAL INFORMATION
Tuning
range
540 -1615
kilocycles
Intermediate
frequency -262
kilqcycles
Maximum power output 4.2
watts
Undlstorted
power output 3.2
watts
Current
drain
1.4
amperes
at
12
volts
Speaker-Alnico
V
permanent
magnet
type 6 x 9
, Inch
Voice
coil
impedance 4
ohms
at
400
cycles
All cl!:
cuits
,!se a
printed
circuit
board

II
,
6V.
o
11.4V
AV
,
10
,
ZV
,
IZV,
OV, 10,ZV. 1.0'1,
{o??\o
0
V
DS~26
10.3V.
·-1.9V,
Figure 84 VOLTAGE
CHART
-985203 -RADIO
PROCEDURE FOR CHECKING THE
VOLTAGES OF 988336 RADIO
Hook up
radio
on
the
service
bench to a "12"
volt
power
supply unit.
It
is
important
that
you
have
12
volts
at
the
spark
plate
of the
radio,
or
the
voltage
readings
will be
correspondingly
lower.
All
voltage
readings
have been
taken
with
V.
T.V.M. Set the
volt-ohm
meter
in
the
"30"
volt
position
to
read
"D.
C."
voltage. Ground one
lead
of volt
meter
to
radio
chassis
and with
other
lead
check
all
tube
pins
marked
"H"
with
a voltage
reading
of
12
volts
as
shown in
Figure
84.
If
incorrect
or
no voltage,
check
or
replace
the
following:
1. Check
or
replace
"On
and
Off"
switch,
Item
55C on
Circuit
diagram
and
55
on
parts
layout.
',
'
,
,
2. Check
or
replace
condensers,
Items
27
and
28 on
circuit
diagram
and
parts
layout.
Next
check
the
transistor
collector
element
marked
"C"
of
the
DS503 output
transistor
which should
read
1.3 to 1.7
volts
D.C.
If
high
or
no voltage, check
or
replace:
1. Check
or
replace
emitter
fuse
resistor,
Item
50
on the
circuit
diagram
and
parts
layout.
2.
Check
or
replace
speaker,
Item
60 on
the
circuit
diagram
and
parts
layout.
90
3. Check
or
replace
output
transformer,
Item
58
on
the
circuit
diagram
and
parts
layout.
4. Check
connector,
Item
59
for
ground to
chas-
sis.
This
is
a
shorting
type
interlock
switch
and
must
be orrened by
speaker
plug when
testing
radio.
5.
Check
or
replace
potentiometer,
Item
57
on
the
circuit
diagram
and
parts
layout.
Next
check
the
resistance
of
the
base
element
of
the
transistor
marked
"B"
of the DS503 to
ground with
the
radio
turned
off. Make
this
check
with
meter
on
the
R x 1 ohm
scale.
The
re
sistance
should be between 2 and
15
ohms.
If
incorrect
or
zero,
check
or
replace:
1. Check
or
replace
the input
transformer,
Item
56
on
the
circuit
diagram
and
parts
layout.
2.
Check
or
replace
condenser,
Item
19B on
the
circuit
diagram
and
parts
layout.
3.
Check
or
replace
reSistor,
Item
51
on the
circuit
diagram
and
parts
layout.
Next
check
the
resistance
to
ground of the
tran-
sistor
emitter
element
marked
"E"
with
the
radio
turned
off. Set the
ohmmeter
on
the
RXI

c B
18
11151
F E
Figure
85
PARTS
LAYOUT
ON
CIRCUIT
BOARD
-985203 -RADIO
scale
.
The
resistance
should
be
between
1 and 4
ohms.
If
inc
orrect
or
zero,
che
ck
or
replace:
1. Che
ck
or
re
place
fu
se re
sistor,
Item
50 on
the
c
ir
c
uit
diagram
and
parts
layout.
2. Che
ck
or
replace
condenser,
Item
19B on
the
circuit
dia
g
ram
and
parts
layout.
Next, with
th
e
radio
turn
ed off,
check
the
re-
,.,
s
istance
be
tween
the
collector
element
i
marked
ue"
and the
emitter
element
marked
~
teE"
of
the
DS503.
If
less
than 1
ohm,
the
transistor
may be
short
ed.
Disconnect
th
e
.
l
~
ads
and
check
the
resistance
again.
If
still
less
than
1 ohm,
replace
the
transistor.
Next
check
the
transistor
collector
element
marked
"c"
of
the
DS26
transistor
which
should
re
ad .5 to 1.0
volts
D.
C.
If
high
or
no
voltage,
check
or
replace:
1. Check
resistor.
2. Check
or
replace
audio
transformer,
Item
56
on
the
circuit
diagram
and
parts
layout.
91
3.
Check
or
replace
condenser,
Item
19A on
the
circuit
diagram
and
parts
layout.
4.
Check
or
replac
e 12AE6A
tub
e.
5.
Check
or
replac
e re
sistor
;
Item
47 on
the
circuit
diagram
and
parts
layout.
6.
Check
or
replace
resistor,
Item
48
on
the
c
ircuit
diagram
'
and
parts
layout
.
Next
check
tube
pin No. 7
marked
"P"
on
the
12AE6A which
should
read
10.2
volts
D.
C.
If
incorrect
or
no
voltage,
check
or
replace:
1.
Check
or
replace
transformer,
Item
56
on
the
circuit
diagram
and
parts
layout.
2. Check
or
replace
resistor,
.
Item
52
on
the
circuit
diagram
and
parts
layout.
Next
check
tube pin
No
. 2
marked
"K"
on
the
12AE6A which
should
read
1.1
volts
D.
C.
If
in-
correct
or
no
voltage,
check
or
replace:
1. Check
or
replace
resistor,
Item
42
on
th
e
circuit
diagram
and
parts
layout.

o
58
67
TUNER
78
10
5503
1
56
CIRCUIT BOARD
(TUBE
VIEW)
~-0526
Figure
86
PARTS
LAYOUT -BOTTOM VIEW -985203 -RADIO
Next
check
tube pin
No.5
marked
"
P"
on
the
12EK6 I.
F.
amplifier
which should
read
11.4
volts
D.
C.
If
incorrect
or
no
voltage,
check
or
replace:
1.
Check
or
replace
1.F.
transformer,
Item
7
on the
circuit
diagram
and
parts
' layout.
'.
•
Next check tube pin
No.
6
marked
"S"
on
the
12EK6 which should
read
11.4
volts
D.C.
If
in-
correct
or
no
voltage, check
or
replace:
1. Check
or
replace
electrolytic
condenser,
Item
19A
on the
circuit
diagram
and
parts
layout.
2.
Check
or
replace
resistor,
Item
52
on
circuit
diagram
and
parts
layout.
Next check tube pin No. 5
marked
"P"
on the
12AD6 which should
read
11.4
volts
D.
C.
If
in-
correct
or
no voltage,
check
or
replace:
1. Check
or
replace
1.
F.
transformer,
Item
6
on the
circuit
diagram
and
parts
layout.
92
Next
check
tube
pin No. 6
marked
"S"
on
the
12AD6 which should
read
11.4
volts
D.C.
If
in-
correct
or
no voltage,
check
or
replace:
1. Check
or
replace
oscillator
coil,
Item
5 on
the
circuit
diagram
and
parts
layout.
Next
check
tube pin No. 5
marked
"P
" on
the
12DZ6
R.F.
amplifier
which should
read
11.4
volts
D.
C.
If
incorrect
or
no
volta
ge, check
or
replace:
1.
Check
or
replace
choke,
Item
3 on
the
circuit
diagram
and
parts
layout.
2. Check
or
replace
condenser,
Item
17A
on the
circuit
diagram
and
parts
layout.
Next check tube pin No. 6
marked
"S"
on the
12DZ6 which should
read
11.4
volts
D.
C.
If
in-
correct
or
no vo
lt
age,
check
or
repla
ce:
1.
'check
or
replace
re
sistor,
Item
52
on
the
circuit
diagram
and
parts
layout.

P
I
Lw
~
fOs503l
b 0
~
I]
I @
= 8 I
56
" ,'Y
~
l
CI
RCU
IT BOARD
(CIRCUIT VI
EW)
TUNER
J
78
\
~~~
~
~
-
II
0
Figure
87
PA
RT
S L
AYO
UT - TOP VI
EW
-985203 -
RAD
IO
PROCEDURE FOR SIGNAL TRACING
RADIO 985203
Turn
on
signal
generator
and
set
in audio
posi-
tion
to
obtain
a 400
cycle
audio
signal.
Ground
one
lead
of
signal
generator
to
radio
Qhassis.
NOTE:
To
protect
the
signal
generat
yr
from
"D.C."
voltage,
place
a 0.1 mfd.
condenser
in
signal
generator
lead
between
the
signal
generator
and
the
end of
the
test
lead.
Adjust
signal
generator
volume
about
3/4
open
to
obtain
a
strong
signal.
With
signal
generator
lead,
touch DS26
collector
marked
"C".
If
no
signal,
check
or
replace:
1. Check
or
replace
fuse
resistor,
Item
50 on
the
circuit
diagram
and
parts
layout.
2.
Check
speaker
interlock
socket,
Item
59.
3.
Check
or
replace
speaker,
Item
60 on
circ
u
it
diagram
and
parts
layout.
93
4. Check
or
replace
the
output
transformer,
Item
58
on
the
circuit
diagram
and
parts
layout.
5.
Check
or
replace
input
transformer,
Item
56
on the
circuit
diagram
and
parts
layout.
6. Check
or
rep
l
ace
DS5
03
transistor
output
stage.
With
signa
l
generator
lead
touch
tube
pin No. 7
maoked
"P"
on
the
12AE6A tube.
If
no
signa
l
check
or
replace
the following:
1. Check
transistor.
2.
Check
or
replace
· 12AE6A tube.
3.
Check
or
replace
resistor,
Item
47
on
circui
t
diagram
and
par
ts layout.
4. Check
or
replace
resistor,
Item
48 on
circuit
diagram
and
parts
layout.

Figure
88
CIRCUIT BOARD ,
PATTERN
-
985203
-RADIO
5.
Check
or
replace
condenser,
Item
19A
on
circuit
diagram
and
parts
layout.
With signal
generator
lead
touch tube pin No. 7
marked
"G"
on
the
12EK6A tube.
If
no
signal,
check
or
replace
the following:
1. Check
or
replace
12AE6A tube
or
tube
socket
on
circuit
diagram
and
parts
layout.
2.
Check
or
replace
resistor,
Item
46
on
circuit
diagram
and
parts
layout.
3.
Check
or
replace
resistor,
Item
42
on the
circuit
diagram
and
parts
layout.
4.
Check
or
replace
condenser,
Item
23
on
the
circuit
diagram
and
parts
layout.
Next
turn
volume
control
all
the way open and
touch tube
pins
No's.
5 and 6
marked
t
'DP"
on
the 12AE6A tube.
If
no
signal,
check
or
replace
the
following:
1. Check
or
replace
12AE6A tube.
2.
Check
or
replace
volume
control,
Item
55A
on
diagram
and
55
on
parts
layout.
Now
change
signal
generator
from
audio
position
to
generate
an
intermediate
frequency
signal.
Set
signal
generator
to .262
kilocycles,
leaving
0.1 mfd.
condenser
in
signal
generator
lead
to
protect
the
signal
'
generator
from
"D.
C."
volt-
age. Keep
signai'
generator
grounded
to
radio
chassis.
94
Next touch tube pin
No.1
marked
"G"
on 12EK6
intermediate
frequency
amplifier
tube.
If
no
signal,
check
or
replace
the
following:
1.
Check
or
replace
12EK6 tube.
2.
Check
or
replace
intermediate
frequency
transformer,
Item
6 on
circuit
diagram
and
parts
layout.
3.
Check
or
replace
12EK6 tube socket.
Next touch tube pin No. 5
marked"
P"
on 12AD6
tube.
If
no
signal,
check
or
replace
the
following:
1. Check
or
replace
intermediate
frequency
transformer,
Item 6 on
circuit
diagram
and
parts
layout.
Next touch tube pin
No.7
marked
"G"
on 12AD6
tube.
If
no
signal,
check
or
replace
the
following:
1. Check
or
replace
12AD6 tube.
2. Check
or
replace
oscillator
coil,
Item
5 on
circuit
diagram
and
parts
layout.
Next change
signal
generator
from
intermediate
frequency
setting
to
radio
frequency
signal.
Re-
place
the
0.1 mfd.
condenser
in the
signal
generator
lead
with a .000082 mfd.
condenser
to
protect
signal
generator
from
"D.
C."
voltage.
Set
signal
generator
to 1100
kilocycles
and tune
radio
receiver
to 1100
kilocycles
(11
on
dial
scale).

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IGNAL
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SIG
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SIG
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POINT SIGNAL STOPS - CHECK OR
REPLACE
ITEMS LISTED
,
,
,
,
,
- ~ -
-
TO
tel
0
10
'1111
'LOCI!
No s
ignal
at
Point
1 - Check
or
rep
la1e
ite
ms No
signal
at
Point
6 -Check
or
r
eplace
19C-
51-50-
56
-58-
60-
69-DS503. .
item
6.
No
signal
at
Point
2 - Check
or
rep
l
ace
ite
ms No
signal
at
Point
7 - Check
or
rep
l
ace
item
19A-47-48-12AE6A
tube-DS26. 5
-1
2AD6 tu
be
or
socket.
No
signa
l at
Point
3 - Check
or
rep
l
ace
ite
ms No
signa
l
at
Poi
nt 8 -
Check
or
replace
items
23-42-46-12AE6A
tub
e.
4-5
-
17A-17B-2
1
A-2
1B.
No
signal
at
Point
4 - Check
or
replace
ite
ms No
signal
at
Point
9 -
Check
or
vepl
ace
item
42-55A-55B-12AE6A
tu
be
or
socket.
3-12DZ6
tube
or
socket.
No
signa
l at
Point
5 - Check
or
rep
l
ace
it
em
7 No
signal
at
Point
10 - Check
or
rep
l
ace
items
or
12EK6 tube
or
sock
et. 1- 2- 16.
Figure
89
SI
GNAL
T
RAC
I
NG
PROCEDURE
-
985203
-
RAD
IO
95

Next touch tube pin
No.5
marked
"P"
on 12DZ6
radio
frequency
amplifier
tube.
If
no signal,
check
or
replace
the following:
1. Check
or
replace
radio
frequency
coil,
Item
4 on
circuit
diagram
and
parts
layout.
2. Check
or
replace
oscillator
coil,
Item
5 on
circUit
diagram
and
parts
layout. .
3. Check
or
replace
condensers,
Items
17A,
20A,
21A
and 21B on
circuit
diagram
and
parts
layout.
4.
Check
or
replace
resistor,
Item
37
on
circuit
diagram
and
parts
layout.
Next touch tube pin
No.1
marked
"G"
on 12DZ6
radio
frequency
tube.
If
no
signal,
check
or
replace
the
following:
1. Check
or
replace
12DZ6 tube.
2. Check
or
replace
12DZ6 tube socket.
3.
Check
or
replace
choke,
Item
3 on
circuit
diagram
and
parts
layout.
Next touch
antenna
terminal
at
antenna socket.
If
no signal,
check
or
replace
the
following:
1. Check
or
replace
antenna
coil,
Item
1 on
circuit
diagram
and
parts
layout.
2.
Check
or
replace
condenser,
Item
16
on
circuit
diagram
and
parts
layout.
3
..
Check
or
replace
choke,
Item
2 on
circuit
diagram
and
parts
layout.
This
completes
the
entire
checking
procedure
of
the
receiver,
and if
the
procedure
has
been fol-
lowed
as
outlined,
the
failure
will have been
located.
After
repairing
"failure,
receiver
will
operate
and shoul(! now
l).e
"aligned
for
proper
performance
as
follows and which
is
part
of
the
service
operation
when'
repairing
radios.
PROCEDURE FOR ALIGNMEN1
OF 985203 RADIO
All
receivers
are
properly
aligned
at
the
factory
and should
require
no
further
adjustments
,
ex-
cept
adjusting,
the
receiver
to the antenna when
installation
is
made,
unless
the
adjustments
have
been
tampered
with,
or
new
coils,
intermediate
frequency
tran
'
sformer,
or
tuning
cores
have
been
installed.
'
To
properly
align
the
receiver,
it
will be
neces-
sary
to have an output
meter
and'
signal
generator.
NOTE :
If
anyone
of
the
tunlllg
coils
or
cores
have been
replaced,
see
"Capacity
and
In-
96
Figure
90
IR<?N
CORE
ALIGNMENT
-985203 -RADIO
ductance Alignment
Procedure"
before
pro-
ceeding with alignment of the
receiver.
If
only
the
adjustments
have
been
tampered
with
or
an
intermediate
frequency
transformer
has
been
replaced,
proceed
with
the
align-
ment
as
follows:
1.
First
hook up an output
meter
to
the
radio
receiver.
Any volt
meter
which will
read
"
A.
C."
can be used. Set
the
voltmeter
in the
t,
3"
volt
"A.
C.
" range position and
place
voltmeter
leads
across
speaker
voice
coil
terminals.
Speaker
is
Item
60
on
circuit
diagram
and
parts
layout.
2.
Turn
on
signal
generator
and
set
adjustments
to obtain a
262
kilocycle
signal. Connect one
lead
of
signal
generator
to
radio
chassis
for
ground.
Attach
the
other
lead
from
the
signal
generator
to
the
tube pin
No.
7
marked"
G"
on 12AD6 tube.
3.
Adjust
signal
generator
volume
control
so
that
the
volt
meter
will
read
,
at
about half
scale.
NOTE: Radio
receiver
volume
control
must
be
turned
to the
maximum
position
so
that
the
automatic
volume
control
circuit
of the
radio
will not
affect
the alignment of
the
receiver.
4.
Adjust in sequence
cores
"A,
B,
C and
D",
as
shown on
circuit
diagram
and
parts
layout,
for
maximum
meter
reading
.
Repeat
adjustments
to
get
maximum
meter
read-
Ing. Keep the
signal
generator
volume tuned
down so
that
during
adjustments
the
meter
does not
read
more
than half
scale.
This

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-l
120Z6
R.
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r
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20
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12A06
OSC.-MDO.
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17
3
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12EK6
I.
F.
AMP
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17
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AUO
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Figure
91
CIRCUIT DIAGRAM -985203 -RADIO

Figure
92
TUNER
AND
DIAL
CORD
VIEW
-
985203
-RADIO
will
result
in a
better
alignment
of
the
receiver.
5.
Next change
signal
generator
setting
to obtain
a
radio
frequency
signal
and tune
signal
generator
to
exactly
1615
kilocycles.
Connect
a .000082 mfd.
condenser
to antenna con-
nector
and
attach
signal
generator
lead. Tune
radio
receiver
to
the
"stop"
on the 1600
kilocycle
end
of
the
dial. Keep tlte
signal
generator
volume
control
adjusted
so
that
output
meter
reads
at
about
half
scale.
6.
Adjust
trimmers
·
"E,
F and
G"
on
circuit
diagram
and
parts
layout in
sequence
for
maximum
readings
on output
meter.
Repeat
for
maximum
meter
readings.
7.
After
the
receiver
has
been
installed
in
the
car,
turn
on
receiver
and tune in a weak
station
near
1000
kilocycles,
with
radio
vol-
ume
control
turned
to
maximum
pOSition
and
the
antenna extended to full height.
Re-
adjust
trimmer
"G" ONLY
for
maximum
volume.
98
CAPACITY AND INDUCTANCE ALIGNMENT
PROCEDURE FOR 985203 RADIO
This
alignment
procedure
is
to be
used
only
when any of the following
parts
have
been
re-
placed
in the
radio;
antenna
coil,
radio
fre-
quency coil,
oscillator
coil
or
any of
the
tuning
cores.
The
intermediate
frequency
alignment
at
262
kilocycles
is
the
same
as
outlined in
"Alignment
Procedure"
operations
1
through
4.
After
com-
pleting
the
intermediate
frequency
alignment,
proceed
as
follows:
1. Connect
signal
generator
lead
to a .000082
mfd. condensep.-and
connect
to antenna
ter-
minal
of antenna socket. T(me
signal
gen-
erator
to
exactly
1615
kilocycles,
and tune
radio
receiver
to
"stop"
on
the
1600 kilo-
cycle
end
of
the
dial.
2.
Adjust output
meter
to
about half
scale,
and
then
adjust
trimmers
"E,
F and
G"
on
cir-
cuit
diagram
and
parts
layout in
sequence
for
maximum
meter
readings.

3.
Next
tune
signal
ge
nerator
and
radio
receiver
to
exactly
600
kilocycles,
approximately
6 on
radio
dial,
and
adjust
iron
cores
"H,
J
and
K"
for
maximum
readings
on
output
meter.
NOTE:
The
iron
cores
are
slotted
so
that
adjustments
can
be
made
with
a
small
insu-
lated
screw
driver
that
fits
loos
ely
in
the
coil
forms.
4.
Repeat
alignment
procedure
at
1615
and
600
kilocycles
until
th
e
maximum
re
a
dings
have
been
attained.
5.
After
the
r
ece
iver
has
been
installed
in
the
car,
turn
on the
receiver
and
tune
in
a
weak
station
near
1000
kilocycles
,
with
radio
vol-
ume
tuned
to
maximum
position
and
antenna
extended
to
full
height.
Readjust
trimmer
rcG"
only for maximum volume.
,.
t
Figure
93
CROSS
SECTION
OF
ESCUTCHEON
-
985203 -
RADIO
SERVICE
PARTS
LIST
985203 RADIO
NOTE:
All
Che
vrolet
radio
se
rvi
ce
parts
are
available
to
d
ea
lers
throu
gh
General
Motors
Parts
Division
Warehouse
s.
Orders
for
radio
parts
requirements
to
be
placed
with
warehouse
in
the
usual
manner.
99
Illus.
No.
Service
Part
No.
Description
ELECTRICAL
PARTS
1
2
3
4
5
6
7
8
16
17
17A
17B
18
19
19A
19B
19C
20
21
21A
2lB
22
23
24
25
27
28
1221138
7255738
7279416
1221138
1221263
1221621
1221622
1221623
7275120
7279808
7272519
7280385
7271042
7273697
7274858
7265426
7280703
7271042
1221509
7257906
36
1214563
37
1214553
38
*1213488
39
*7273602
40 1214564
41
*1213217
42 1213224
43 *1214566
44 *1213488
45 *1213270
46 *1214564
47 *1216128
48 1213224
49 *7280230
50 7276499
51
7271133
52
*1214540
*Not
serviced
COILS
Antenna,
tuning
Choke,
antenna
series
Choke/
Resistor
Shunt,
RF
plate
R.F.
,
tuning
Oscillator,
tuning
1st
I.F.
2nd I.
F.
Choke
"A"
supply,
input
CAPACITORS
Antenna
Trimm
er
Dual
Ceramic
•000027
mid
., 500
volt
.000043
mid.,
500
volt
.047
mfd.,
75
volt,
tubular
Electrolytic
- 3
section
400
mfd.,
16
volt
850
mid.,
16
volt
12
mid.,
11.5 RMS
.1
mid
., 75
volt,
tubular
Dual
Trimmer
R.
F.
Section
Osc.
-Mod.
Section
.000033
mfd
.,
500
volt,
ceramic
.002
mid.,
500
volt
,
ceramic
.0047
mid.,
500
volt,
ce
ramic
.1
mid
.,
75
volt,
tubular
Spark
Plate
.
47
mid.,
100
volt,
tubular
RESISTORS
2.2
megohm
, 1/ 2
watt
47,000
ohm,
1/ 2
watt
680,000
ohm,
1/ 2
watt
39
megohm,
1/ 2
watt
3.3
megohm,
1/ 2
watt
100
ohm,
1/ 2
watt
330
ohm,
1/ 2
watt
4.7
megohm
, 1/ 2
watt
680,000
ohm,
1/ 2
watt
100,000
ohm,
1/ 2
watt
3.3
megohm,
. 1/ 2
watt
3900
ohm,
1/ 2
watt
330
ohm,
1/ 2
watt
4700
ohm,
1/ 2
watt
.33
ohm,
Fuse
Resistor
10
ohm,
1/ 2
watt
56
ohm,
1/ 2
watt

mus.
No.
55
55A
55B
55C
56
57
58
59
60
61
63
64
65
66
67
68
71
72
Service
Part
No.
Description
TUBES
AND
TRANSISTORS
1221649
1221126
1220987
1221272
1221628
1221625
*1221643
DS26
Transistor,
audio
driver
12DZ6Tube,
R.F.
Amp.
12AD6 Tube,
osc.-mod.
12EK6
Tube,
I.
F. Amp.
12AE6A
Tube,
audio-det.
DS503
Transistor,
output
Hardware-Insulator
Kit,
mtg.
MISCELLANEOUS
ELECTRICAL
7280349
Control,
vol.,
tone
&
switch
7277230
7275474
1221535
7274985
7277515
456985
Volume
Tone
Switch
Transformer,
input
Rheostat,
260
ohms,
T.C.
Transformer,
output
SWitch,
speaker
inter-lock
Speaker,
6 x
9",
P.M.,
slotted
Lamp,
dial
light, #1891
MECHANICAL PARTS
7275571
7278950
7280898
7269576
1221114
7268815
7275106
7274916
CHASSIS
Dial
Light
Assembly
Lead
&
Plug
Assembly,
speaker
Radiator
Pkg.,
transistor
heat
Shield,
tube
Socket,
antenna
connector
Socket, tube,
7-pin
miniature
TUNER
0,
t
Backplate,
pOinter
Bushing,
manual
shaft
*Not
serviced
100
Illus.
No.
73
74
75
76
77
78
78A
78B
79
80
81
82
83
84
85
86
Service
Part
No.
1219143
7274289
7273859
1221510
7274917
7280000
7258565
7258564
7271590
7271505
7272125
7263593
7269225
72~2922
Description
Cord,
dial
pOinter
drive
Core
Bar
Core,
tuning
Drive
Shaft,
manu
al
Spring,
shaft
retainer
Escutch
eon
Assembly
Backplate,
dial
Dial,
calibrated
Gromm
e
t,
ant. &
R.
F.
coils
mtg.
Grommet,
osc.
coil
mtg.
Housing, tuning
coils
Sleeve,
ant. &
R.
F.
coils
Pointer
Assembly
Pkg.
Pulley,
dial
cord
Spring,
dial
cord
tension
Spring,
manual
drive,
friction
INSTALLATION PARTS
3783236
3783238
7259643
1947452
7259643
3798240
3783307
148511
7277055
7274782
7272970
7235969
3784324
7276494
2974198
3797526
7257400
445347
Brack
et,
radio
mounting
Bracket
,
radio
cover
Capacitor,
generator
Capacitor,
ignition
coil
Capacitor,
voltage
regu
lator
Cover
Assembly,
radio
Cushion,
speaker
mt
g.
bracket
Fuse,
4 Amp.,
type
AGC
Knob,
control
(2)
Knob,
dummy
Knob, tone
control
Nut,
radio
bushing
(2)
Plate,
speaker
mt
g.
Static
Collector,
front
wheel
(2)
Strap
,
radio
ground,
5" long (2)
Trimpl
ate
Wash
er,
wave, knob
anti-
rattle
(2)
Nut,
It
J"
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