
PHOTOFACT*
Folder
DISASSEMBLY
INSTRUCTIONS
CHASSIS
REMOVAL
1.
Remove
4
push-ontypeknobs
from
the
front.
2.
Remove
6
metal
screws
from
the
rear
cover.Remove
the
rear
cover.
3.
Remove
4
metal
screws
holding
the
tuner.Remove
the
tuner.
4.
Remove
2
metalscrewsholding
the
controlbracket.
5.
Remove
the
speaker
leads.
6.
Remove
4
chassis
bolts
from
the
bottom.
7.
Remove
the
chassis.
MODEL
A2221YlCh.
17A20)
TRADE
NAME
Zenith
MODELS
CHASSIS
MANUFACTURER
TYPE
SET
TUBES
POWER
SUPPLY
TUNING
RANGE
A2221J,
Y,
A2223E,
H,R,Y,
A2245E,
R,
A2250M,
R,
A2251E,
R,
A2282E,
R,
A2673E,
R
17A20
A2221JU,
YU,
A2223EU,
HU,RU,YU,
A2245EU,
RU,
A2250MU,
RU,
A2251EU,
RU,
A2282EU,
RU,
A2673EU,
RU
17A20U
A3001E,
H,R,
A3006E,
H,R,
A3008E,
R
17A20Q
A3000E,
R.
A3004,
E,R
17A21Q
Zenith
Radio
Corp.,
6001
Dickens
Avenue,Chicago
39,
Illinois
Television
Receiver
Seventeen
110-120
Volts
AC,60
CycleRATING
185
Watts,
1.6
Amp.
© 117
Volts
AC
Channels
2
thru
13
VHF,
14
thru
83
UHF,Video
IF45.
75MC,Sound
IF41.
25MC
(Intercarrier)
SERVICING
INTHE
FIELD
TUNER
OSCILLATOR
ADJUSTMENTS
Touch-up
adjustment
oftheVHF
oscillator
is
possible
by
removing
the
channel
selector
and
fine
tuningknobs.
Set
the
fine
tuning
atthe
center
ofits
range.
The
adjustments
(located
ina
circle
around
the
shaft)
should
be
made
inse-
quence
from
the
highest
tothe
lowestchannel
inthe
area.
Channel
13
adjustment
is
located
at12
o'clock,proceed
in
a
counterclockwisedirectionadjusting
for
best
picture
and
sound.
PICTURE
TUBE
SAFETY
GLASS
CLEANING
Remove
4
push-ontypeknobs
from
the
front.Remove
4
metal
screws
holding
knob
escutcheons.
Tilt
the
safety
glass
outatthetopand
lift
to
remove.
SPECIAL
ADJUSTMENTS
A.
AGC
Observe
the
picture
and
advance
theAGC
control
toa
point
where
the
picture
distorts
ora
buzz
is
heard
inthe
sound.
Back
off
from
this
setting
until
the
picturebecomes
stable
with
no
noise
inthe
sound.
B.
FringeLock
Turn
the
fringelockcontrol
fully
clockwise,
then
counter
clockwiseapproximately
1/4
turn.
Adjust
picture
to
lock
in
with
hold
controls.
If
picture
jitters,
tears,
etc.
adjust
fringe
lockcounterclockwiseuntil
stable.
Readjust
hold
controls
and
checkoperation
onall
channels
inthe
area.
C.
Focus
The
focus
maybe
varied
by
means
ofa
focus
control.
(For
location,
see
tubeplacementchart).
D.
Width
The
width
maybe
varied
by
menas
ofa
metallic
sleeve
lo-
catedbetween
the
yoke
andthe
picturetubeneck.
Adjust
sleeve
inoroutofthe
yoke
fora
picture
SLIGHTLY
larger
than
necessary
to
fill
the
screen.
HORIZONTAL
OSCILLATOR
FIELD
ADJUSTMENTS
The
horizontal
oscillator
coil
is
used
asthe
horizontalhold
control.
Adjust
the
horizontalhold until
the
picture
syn-
chronizeshorizontally.(Forlocation,
see
tubeplacement
chart).
SOUND
IF
DETECTOR
BUZZ
ADJUSTMENT
To
eliminateaudio
detector
buzz,adjust
the
buzzcontrol
for
MINIMUM
buzz
and
maximumsound.(Forlocation,
see
tubeplacement
chart).
FUSES
One
fuse
is
used
for
horizontalsweep
circuit
protection.
(For
location,
see
tubeplacementchart).
CENTERING
Centering
is
accomplishedmechanically
by
adjusting
two
magnetic
rings
around
the
neck
ofthe
picturetube.Rotate
the
two
rings
around
the
neck
ofthe
tubeuntil
the
picture
is
properlycentered.
HOWARD
W.
SAMS
&
CO.,INC.
The
listing
ofany
availablereplacementparthereindoes
not
constitute
inany
case
a
recommendation,warranty
or
guaranty
by
Howard
W,
Sams
&
Co.,
Inc.,
astothe
quality
and
suitability
of
suchreplacementpart.
The
numbers
of
theseparts
have
beencompiled
from
information
furnished
to
Howard
W.
Sams
Si
Co.,
Inc.,
bythe
manufacturers
of
H389
•
Indianapolis
5,
Indiana
the
particular
type
of
replacementpartlisted.Repro-
duction
or
use,
without
expresspermission,
of
editorial
or
pictorialcontent,
inany
manner,
is
prohibited.
No
patent
liability
is
assumed
with
respect
totheuseofthe
informa-
tion
contained
herein.
©
1958
Howard
W.
Sams
&Co.,
Inc.,
Indianapolis
5,
Indiana
.
Printed
in
U.S.
of
America
o
o
m
70
DATE
3-58
SET
393
FOLDER
4