LG 32FS4D, 30FS4D Schematic
COLOR TV
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS : AC-05MB
MODEL : 30FS4D 32FS4D-UC
CANADA : http//biz.lgservice.com
USA : http//www.lgservice.com
: http//biz.lgservice.com
- 2 -
SAFETY PRECAUTIONS
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in
the Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to
prevent X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance
An lsolation Transformer should always be used during
the servicing of a receiver whose chassis is not isolated from
the AC power line. Use a transformer of adequate power rating
as this protects the technician from accidents resulting in
personal injury from electrical shocks.
It will also protect the receiver and it's components from being
damaged by accidental shorts of the circuitary that may be
inadvertently introduced during the service operation.
If any fuse (or Fusible Resistor) in this TV receiver is blown,
replace it with the specified.
When replacing a high wattage resistor (Oxide Metal Film
Resistor, over 1W), keep the resistor 10mm away from PCB.
Keep wires away from high voltage or high temperature parts.
Due to high vacuum and large surface area of picture tube,
extreme care should be used in handling the Picture Tube .
Do not lift the Picture tube by it's Neck.
X-RAY Radiation
Warning:
To determine the presence of high voltage, use an accurate
high impedance HV meter.
Adjust brightness, color, contrast controls to minimum.
Measure the high voltage.
The meter reading should indicate
23.5
!1.5KV: 14-19 inch, 26!1.5KV: 19-21 inch,
29.0
!1.5KV: 25-29 inch, 30.0 ! 1.5KV: 32 inch
If the meter indication is out of tolerance, immediate service
and correction is required to prevent the possibility of
premature component failure.
Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
metallic parts of the cabinet, such as antennas, terminals, etc.,
to be sure the set is safe to operate without damage of
electrical shock.
Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source,
connect an electrical jumper across the two AC plug prongs.
Place the AC switch in the on positioin, connect one lead of
ohm-meter to the AC plug prongs tied together and touch other
ohm-meter lead in turn to each exposed metallic parts such as
antenna terminals, phone jacks, etc.
If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1MΩ and 5.2MΩ.
When the exposed metal has no return path to the chassis the
reading must be infinite.
Any other abnormality that exists must be corrected before the
receiver is returned to the customer.
Leakage Current Hot Check (See below Figure)
Plug the AC cord directly into the AC outlet.
Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Measure the AC voltage across the resistor using AC
voltmeter with 1000 ohms/volt or more sensitivity.
Reverse plug the AC cord into the AC outlet and repeat AC
voltage measurements for each esposed metallic part. Any
voltage measured must not exceed 0.75 volt RMS which is
corresponds to 0.5mA.
In case any measurement is out of the limits sepcified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
Leakage Current Hot Check circuit
CANADA: LG Electronics Canada, Inc. 550 Matheson
Boulevard East Mississauga, Ontario L4Z 4G3
USA : LG Customer Interactive Center
P.O.Box 240007, 201 James Record Road
Huntsville, AL 35824
Digital TV Hotline 1-800-243-0000
The source of X-RAY RADIATION in this TV receiver is the
High Voltage Section and the Picture Tube.
For continued X-RAY RADIATION protection, the
the Replacement Parts List.
IMPORTANT SAFETY NOTICE
0.15uF
To Instrument’s
exposed
METALLIC PARTS
AC Volt-meter
Good Earth Ground
such as WATER PIPE,
CONDUIT etc.
1.5 Kohm/10W
- 3 -
DESCRIPTION OF CONTROLS...........................................4
SPECIFICATIONS.................................................................9
ADJUSTMENT INSTRUCTIONS ........................................10
PRINTED CIRCUIT BOARDS.............................................22
BLOCK DIAGRAMS............................................................29
EXPLODED VIEW...............................................................32
EXPLODED VIEW PARTS LIST.........................................33
REPLACEMENT PARTS LIST............................................34
SCHEMATIC DIAGRAMS.......................................................
TABLE OF CONTENTS
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Front Panel Controls
ON/OFF
Standby indicator (Illuminates brightly when the TV is in
standby mode. Dims when the TV is switched on.)
Remote control sensor
TV/VIDEO
MENU
VOL left/ right
Volume(
GG
) button increases the sound level and vol-
ume(
FF
) button decreases the sound level.
CH (Channel) up / down
1
2
3
4
These buttons work just as they do on
your remote control.
5
6
7
ON/OFF
MENU
VOL
CH
TV/
VIDEO
1
2
3
4
5
6
7
DESCRIPTION OF CONTROLS
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Rear Connections Panel
Mini glossary
JACK A connection on the back of a TV, VCR, or any other A/V device. This includes the RF jack and the Audio/Video jacks that are
color-coded.
SIGNAL Picture and sound traveling through cable, or over the air, to your television screen.
CALIBRATION
DIGITAL
AUDIO OUTPUT
OPTICAL
DVD/DTV INPUT
AUDIO
L(MONO)
CABLE
ANTENNA
HDMI/DVI
DIGITAL
AUDIO INPUT
OPTICAL
(DVI)
R
COMPONENT1
(480i/480p/720p/1080i)
COMPONENT2
S-VIDEO
MONITOR
OUTPUT
IN1
IN2
AUDIO
R
AUDIO
AUDIO
INPUT
VARIABLE
AUDIO
S-Video In
A connection available with some highend equipment that
provides even better
picture quality for
Video 1, Front Video.
RF Connectors:
Cable, Antenna
Used to connect
cable or antenna
signals to the television, either directly
or through your
cable box.
Video 1 and 2 Inputs
Connects the video signals from various types
of equipment.
Y, P
B, PR
DVD Component Video and HD
Component Video
Some top-of-the-line DVD players
use what is called “component
video,” for extremely accurate picture reproduction. Refer to your
DVD manual for further information.
Connecting external equipment to your TV.
Monitor Out
Connects to a second TV or Monitor.
Left/Right Audio
Used for stereo sound
from various types of
equipment.
Component Left/Right
Audio
Used for stereo sound
from various types of
equipment.
HDMI/DVI
Used to connect
from a DTV
source.
Digital Audio
Output Optical
Connects to exter-
nal audio equip-
ment like a home
theater system.
Digital Audio Input
Optical
Connects to digital
audio from various
types of equipment.
DESCRIPTION OF CONTROLS
C
A
L
I
B
R
A
T
I
O
N
DIGITAL
AUDIO OUTPUT
OPTICAL
DIGITAL
AUDIO INPUT
OPTICAL
(DVI)
HDMI
/DVI
CABLE ANTENNA
+75 Ω +75 Ω
COMPONENT1
COMPONENT2
(480i/480p/720p/1080i)
(R)
AUDIO
(L)
P
R
PB
Y
DVD/DTV INPUT
CALIBRATION
DIGITAL
AUDIO OUTPUT
OPTICAL
DIGITAL
AUDIO INPUT
OPTICAL
(DVI)
HDMI/DVI
AUDIO
CABLE
ANTENNA
++7575 ΩΩ ++7575 ΩΩ
COMPONENT1
COMPONENT2
(480i/480p/720p/1080i)
RR
RR
AUDIO
AUDIO
AUDIO
LL
LL
VIDEOVIDEO
L(MONO)
RR
VARIABLE
MONITOR
AUDIO
PP
R
R
PP
OUTPUT
S-VIDEO
LL
PP
BB
PP
BB
IN2
INPUT
AUDIO
RR
YY
YY
IN1
DVD/DTV INPUT
(R)
(L)
PR
S-VIDEO
INPUT
PB
Y
VIDEO
AUDIO
L(MONO) R
MONITOR
OUTPUT
IN2
IN1
- 6 -
Side Connections Panel
There are four jacks on the lower-right front side
of your TV that make connecting Audio/Video
devices like video games and camcorders very
simple.
The jacks are like those found on the back jack
connection panel. This means that most equipment that connects to those types of jacks on
the rear jackpack, may be connected to the Side
connection panel (FRONT VIDEO).
To use the Side jacks as the signal source,
select them using Input source menu as
described on page 25. They will be named
“FRONT VIDEO” in the Input source menu.
Left/Right Audio
Used for stereo sound
from various types of
equipment.
Video in
Connects the video
signals from any
piece of equipment.
S-Video
A connection available on some very
high-end equipment that provides
better picture quality than video
input.
When you select Front Video
or Front S-Video, the Front
Audio inputs are automatically
selected as well.
Do not connect to both Video
and S-Video at the same time.
Connect either Video or SVideo only.
Mini glossary
A/V CABLES Audio/Video cables. Three cable connector—Right audio (red), Left audio (white), and Video (yellow). A/V cables are used
for stereo playback of videocassettes and for higher quality picture and sound from other A/V devices.
A/V DEVICE Any device that produces video (picture) and/or audio (sound) (VCR, DVD, cable box, or television).
DESCRIPTION OF CONTROLS
FRONT VIDEO Panel
S-VIDEO
VIDEO IN
L/MONO
AUDIO
R
FRONT VIDEO
- 7 -
Remote Control Functions in TV Mode
FAV
Use to scroll the FAV channel list.
MENU
Brings up the main
menu to the screen.
EXIT
Clears all on-screen displays and returns to TV
viewing from any menu.
CC
Lets you select a closed caption
mode for displaying captioning
information when provided for
DTV/Analog signal.
EZ PIC
Adjusts the factory preset picture depending on the viewing environment.
SAP
Selects MTS sound: Mono, Stereo,
and SAP in analog mode.
Change the audio language in DTV
mode.
SURROUND
Selects : Off, 3D
EchoSound System and
SRS TruSurround XT.
MUTE
Switches the Mute or the EZ mute.
Mute: The sound is off. EZ mute:
Turns the sound off, and displays the
caption.
THUMBSTICK
(UP/DOWN/LEFT/RIGHT/ )
Allows you to navigate the on-screen
menus and to adjust the system settings
and preferences, by moving to an option
with
F G
and selecting the highlighted
option with .
TV INPUT
Switches TV mode or CATV
mode.
MODE
Selects the remote operating
mode: TV, VCR, Cable, DVD or
Satellite. Select other operating
modes, for the remote to oper-
ate external devices.
TV/VIDEO
Selects: Antenna, Cable,
Video1, Video2, Front video,
Component 1-2 and HDMI/DVI
input sources.
COMP1
Selects the Component 1
input source.
EZ SOUND
Selects the sound appropriate
for the program’s category.
FREEZE
Captures and freezes
the currently-viewed
picture.
RATIO
Changes the aspect ratio.
MODE INDICATOR
LIGHTS
Show active remote mode
every time any button is
pressed.
D
E
DESCRIPTION OF CONTROLS
CABLE
VCR
TV
MODE
TV INPUT
*
TV/VIDEO
HDMICOMP2
1 2 3
4 5 6
7 8 9
DASH(-)
MUTE
EZ SOUND
RATIO
INFO
MENU EXIT
PLAY
REW
0
VOL
TIMER CC
PAUSE
STOP
FF
CH
SKIP
DVD
SAT
POWER
COMP1
FRONT
FLASHBK
FAV
EZ PIC
SURROUNDFREEZE SAP
SIGNAL
RECORD
- 8 -
Remote Control Functions in TV Mode
POWER
Turns your TV or any other
programmed equipment on
or off, depending on mode.
CHANNEL UP/DOWN
Scrolls through available channels
present in EZ Scan memory.
NUMBER KEYPAD
For direct channel selection and
programming functions.
ENTER
When in the menu system
and other on-screen displays, selects highlighted
options.
RECORD, PAUSE, REW,
FFWD, PLAY, STOP
Control the functions on your VCR.
VOLUME UP/DOWN
Increases/decreases the sound
level.
INFO
When you watch the TV, displays
information on top of the screen.
Not available in Component 1-2
and HDMI/DVI.
SKIP LEFT/RIGHT
Playing CDs: Selects
songs.
Playing DVDs: Selects
movie chapters.
COMP2
Selects the Component 2 input
source.
HDMI
Selects the HDMI input source.
DASH(-)
Is used to enter a program
number for multiple program
channels such as 2-1,2-2,etc.
FLASHBK
Tunes to the previous channel
viewed.
TIMER
Lets you select the amount
of time before your TV
turns itself off automatically.
SIGNAL
Displays the digital signal
strength.
FRONT
Selects the front video
input source.
DESCRIPTION OF CONTROLS
VCR
TV
MODE
TV INPUT
TV/VIDEO
1 2 3
4 5 6
7 8 9
DASH(-)
MUTE
EZ SOUND
VOL
RATIO
TIMER CC
INFO
HDMICOMP2
*
0
CABLE
DVD
SAT
POWER
COMP1
FRONT
FLASHBK
FAV
EZ PIC
CH
SURROUNDFREEZE SAP
SIGNAL
MENU EXIT
PLAY
PAUSE
STOP
REW
FF
RECORD
SKIP
- 9 -
Model 32FS4D-UC
Horizontal Size (inches) 36.14
Height (inches) 16.51
Thickness (inches) 23.13
Weight (pounds) 114.9
Power requirement AC 120V~ 60Hz
Television system American TV Standard, NTSC-M, Integrated ATSC tuner, 64 & 256 QAM
Television Channel VHF: 2 - 13
UHF: 14 - 69
CATV: 1 - 135
CADTV: 1 - 135
DTV: 2 - 69
Power consumption (W) 180W
Antenna 75 ohm external terminal for VHF/UHF
Audio Output (W) 7.5W x 2
Supplied accessories Remote control, batteries 2 size AA(Alkaline battery)
Screen Aspect Ratio 16 : 9
External input ports Video/Audio input (3 set)
Video output (1 set)
S-Video input (2)
Component input (2 set)
HDMI/DVI input (1)
Digital audio optical input (DVI)(1)
Digital audio optical output (1)
Calibration port (1)
Cable/Antenna port
Design and specifications are subject to change without prior notice.
Product Specifications
SPECIFICATIONS
- 10 -
1. Application Object
These instructions are applied to the AC-05MB chassis.
2. Notes
(1) Because this is not a hot chassis, it is not necessary to use
an isolation transformer. However, the use of an isolation
transformer will help protect test instruments.
(2) Adjustments must be done in the correct order.
(3) The input voltage of the receiver must remain at
120V±10% while adjusting.
(4) The receiver must be operated for about 20 minutes prior
to the adjustment.
[ Never operate the set over 10 minutes with a still picture
because it may cause screen burn.
3. CPLD Download
3-1. Required Test Equipments &
Preparation for Adjustment
(1) Connect the PC and memory JIG as shown in <Fig. 1>.
(2) Turn on JIG MAIN POWER SW.
(3) Turn on the PC and monitor, operate the ‘Device
Programming’ software.
3-2. Adjustment Sequence
(1) Once the program is running, [OPTION MODE
SELECTION] is displayed in the window.
Check the “Load configuration File(.cdf, .pdr)” in this
window and click the finish button
(2) When the screen displays the open window, select the
suitable file(*.cdf) according to model.
(3) IC figure is change to green by clicking it.
(4) Select program options.
(5) Check the [Erase before programming] and [Verify] menu
as shown <Fig. 2> and press the OK button.
(6) At this time, the download starts. The download will finish
in about 10 seconds.
4. Hold down Operation Check
(1) This check step is implemented during the frame assembly
process.
(2) Check method: Short circuit the R1471 of Main2 JP
display part and check if it switches to ST-BY. (Install 30K
resistances in parallel to the R1471 on jig.)
5. EDID Data Input
5-1. Required Test Equipment
(1) PC, Jig for adjusting DDC. (256 bytes write)
(2) S/W for writing DDC(EDID data write & read)
5-2. Setting of Device
5-3. Adjustment
(1) Set devices as above and turn on the PC and JIG.
(2) Open S/W for writing DDC (EDID data write & read).
(3) Enter the Model-->Open in the Menu and then select EDID
DATA.
(4) Click the Digital and cancel the ANALOG.
Then connect to turn on the yellow light at the board &
connection.
(5) Click the Write Data & Verify and then download the EDID
DATA.
ADJUSTMENT INSTRUCTIONS
<Fig. 1 > How to connect the MEMORY JIG and PC
<Fig . 2>
PC
JIG
TV
SET
<Fig . 3>
- 11 -
6. Focus Adjustment
(1) Set Picture condition to “Normal”.
CONTRAST : 100
BRIGHT : 60
Normal TINT : 60
COLOR : 0
SHARPNESS : 60
(2) Set the Aspect ratio to Wide Mode.
(3) Receive a Cross Hatch Pattern, adjusting the FOCUS
Knob on the flyback transformer for the best focus in the
area designated “A” above.
[ Heat run over 15 minutes before adjustment.
7. CUT-OFF Adjustment
(Screen Voltage Adjustment)
7-1. Test equipment
Oscilloscope, 100:1 Probe
7-2. Adjustment
(1) Select EZ Adjust 3. CUT-OFF, by pressing the ADJ key on
the SVC Remote control.
When it enters to adjustment mode, the pattern from a
signal generator is being selected, it becomes with Normal
image 16:9 and the CUT-OFF DRIVE data setting 31.
(2) Connect the oscilloscope ground lead to GND on the CPT
board and the probe to the GK pin connector of the CPT
socket.
Using the SCREEN knob on the Flyback Transformer,
adjust the black level voltage to 170±2V.
8. Deflection Adjustment
8-1. Preliminary Steps
Select EZ Adjust 1. Raster, Cent, H/V Size by using the ADJ
key on the SVC Remote control.
In the adjustment mode a Digital Pattern signal, NORMAL,
16:9 Screen is displayed.
8-2. Raster V-Center(V.Center) Adjustment
Select 62. V-Postition in the adjustment mode and adjust it to
position the vertical center line in vertical center of the CPT.
8-3. Vertical Deflection Size Adjustment
(Overscan : 10%)
(1) Select 59. V-SIZE in the adjustment mode.
(2) Adjust until the smaller inscribed circle coincides with the
outer frame of screen.
(3) Select 95. LO-VLIN or 94. UP-VLIN and adjust until the
larger inscribed circle coincides with the outer frame of
screen.
ADJUSTMENT INSTRUCTIONS
170±2V
<Fig . 6> CUT-OFF Adjustment
(SCREEN voltage adjustment OSCILLOSCOPE,
100:1 PROBE, VOLTS/DIV : 0.5V/DIV SEC/DIV : 5us,
The TRIGGER MODE it puts in the TV-H)
<Fig . 4>
<Fig . 5>
- 12 -
8-4. Raster H-center(H.CENTER) Adjustment
Select 77. H Postion in the adjustment mode and adjust until
left and right screen are symmetrically equal.
8-5. Horizontal Deflection Size Adjustment
(1) Reduce 66 H-Size to verify screen protection (overscan)
on the right and left sides.
(2) Adjust the horizontal size, using a test pattern.
8-6. Horizontal Pincushion Adjustment
(1) Select EZ Adjust 2. Pin-Cushion(16:9) by pressing the ADJ
key on the SVC Remote control.
In the adjustment mode a Cross-Hatch Pattern, 16:9
Screen is displayed.
(2) Select PIN-PHASE, PIN-AMP, AFC-BOW, AFC-ANGLE,
UP-CPIN, LO-CPIN in the adjustment mode and adjust
until there is no Pincushion distortion or trapezoid distortion
on the screen.
8-7. HRS Switch Adjustment
(1) Change the Cross Hatch Pattern.
(2) If the linearity size width of A is narrow on the A or B,
change the SW1401 to the right.
And if the B is narrow, change the SW1401 to the left to
make the size width as same as A and B.
* If the neutral condition is alike, not to change, put the
position.
(3) Readjust the “1.Raster, Cent, H/V Size“ by pressing the
ADJ key of adjustment remote control.
(4) Readjust the “2.Pin-Cushion(16:9)“ by pressing the ADJ
key of adjustment remote control.
8-8. Pincushion Adjustment (4:3 Mode)
(1) Change the Digital Pattern.
(2) Select EZ Adjust 3. Pin-Cushion(4:3) by pressing the ADJ
key on the SVC Remote control.
In the adjustment mode a Digital Pattern signal, NORMAL,
4:3 Screen is displayed.
(3) 4:3 Pin cushion Adjustment
Adjust the 4 adjustment item to be straight without distortion
left/right line of 4:3 Screen
1) 4 Adjustment Item: Pin-Amp, Pin-Phase, Up-Cpin, LoCpin
2) Initial Data of 4 Adjustment Item: 0
9. Component MST3000 Offset/Gain
Adjustment
9-1. Test Equipment
801GF(802B, 802F, 802R) Pattern Generator or MASTER
Pattern Generator
9-2. Preliminary Steps
(1) Turn the power supply on.
(2) Enter the Component mode.
(3) Receive the “1080I” Format, “Hoz30Bar” Pattern of the
Video Pattern Generator.
(4) Certainly, adjust the output signal in state of 700mVp-p
±10mV.
ADJUSTMENT INSTRUCTIONS
L-LIN U-LIN
A(Left) B(Right)
This screen is reflected picture
at the position of worker
RightLeft
Neutrality
<Fig . 7>
<Fig . 8>
100% White
100% Yellow
100% Cyan
30% Gray
30% Gray
100% Red
100% Blue
Black
<Fig . 9> 1080I Format, Hoz30Bar Pattern
- 13 -
9-3. ADC Offset Adjustment
(1) After receiving a signal press the ADJ Key on the SVC
Remote Control repeatedly to acess the Adjustment mode.
(2) Adjustment will set the automatically by pressing the
“8.MST3000-Set” of adjustment item.
(3) After finishing the adjustment, output the “MST3000-OK”
OSD on the screen.
10. White Balance Adjustment
10-1. Preparation for Adjustment
(1) Perform the Screen Voltage Adjustment first.
(2) The White Balance it executes from automatic adjustment
hour Normal image condition.
(3) Start adjustments from initial setting of R.DRIVE=31,
G.DRIVE=31, B.DRIVE=31, R.CUT=31, G.CUT=31,
B.CUT=31.
(4) For manual adjustment, refer to the following procedure.
10-2. Adjustment
(1) Receive the White Pattern.
(2) Set screen size to wide mode(16:9).
(3) Select EZ Adjust 2.White Balance by pressing IN-START
Key on the SVC Remote control.
(4) Adjustment
1) Using the SVC Remote control, set the DCOL value of
CXA2150 to the “0”.
2) Set an image with Normal image.
3) Adjust R-DRIVE and B-DRIVE data so the color
coordinates in High light are the values in Table below.
(Bright Level : 35fl)
4) Adjust “CONTRAST” and “BRIGHT” so the bright level is
4.5±0.5F.L.
5) Adjust R-CUT and B-CUT data so the color coordinates
in Low light are the values in Table below.
6) Repeat 2)~ 5) until the color coordinates in High and
Low color satisfies the Table.
7) Check the adjusted color coordinates with the white
balance meter.
High Light : x=287
!
3, y=293!3
Low Light : x=287
!
3, y=293!3
Color temperature : 9,000K!
1000(-5MPCD)
11. Sub Bright, TINT, COLOR
Adjustment
11-1. Sub Bright Adjustment
(1) Select EZ Adjust 5. Sub Bright pressing ADJ key on the
SVC Remote control.
(2) Adjust to the point where “2” is not visible.
(3) Completed the adjustment, exit the adjustment mode using
ADJ Key.
11-2. Sub COLOR, TINT Adjustment
(1) Select EZ Adjust 6. Sub Tint, Color pressing ADJ key on
the SVC Remote control.
(2) Select SUB COLOR and adjust the 1 and 1’ portion not to
be classified.
(3) Select SUB TINT and adjust the 3 and 3’ portion not to be
classified.
(4) Completed the adjustment, exit the adjustment mode using
ADJ Key.
ADJUSTMENT INSTRUCTIONS
WHITE
B M C WBK BK BK
1
1'
3
3'
GREEN
MAGENTA
CYAN BLUERED
YELLOW
0 12 34 5 76 8 9
US14CH
- 14 -
PURITY & CONVERGENCE ADJUSTMENT
Caution:
Convergence and Purity have been factory aligned. Do not
attempt to tamper with these alignments.
However, the effects of adjacent receiver components, or
replacement of picture tube or deflection yoke may require the
readjustment of purity and convergence.
¯ Purity Adjustment
This procedure DOES NOT apply to bonded yoke and picture
tube assemblies.
The instrument should be at room temperature (60 degrees F or
above) for six (6) hours and be operating at low beam current
(dark background) for approximately 20 to 30 minutes before
performing purity adjustments.
CAUTION: Do not remove any trim magnets that may be
attached to the bell of the picture tube.
1. Remove the AC power and disconnect the internal
degaussing coil.
2. Remove the yoke from the neck of the picture tube.
3. If the yoke has the tape version beam bender, remove it and
replace it with an adjustable type beam bender (follow the
instructions provided with the new beam bender)
4. Replace the yoke on the picture tube neck, temporarily
remove the three (3) rubber wedges from the bell of the
picture tube and then slide the yoke completely forward.
5. Reconnect the internal degaussing coil.
6. Position the beam bender locking rings at the 9 o'clock
position and the other three pairs of tabs (2,4 and 6 pole
magnets) at the 12 o'clock position.
7. Perform the following steps, in the order given, to prepare the
receiver for the purity adjustment procedure.
a. Face the receiver in the "magnetic north" direction.
b. Externally degauss the receiver screen with the television
power turned off.
c. Turn the television on for approximately 10 seconds to
perform internal degaussing and then turn the TV off.
d. Unplug the internal degaussing coil. This allows the
thermistor to cool down while you are performing the purity
adjustment. DO NOT MOVE THE RECEIVER FROM ITS
"MAGNETIC NORTH" POSITION.
e. Turn the receiver on and obtain a red raster by increasing
the red bias control (CW) and decreasing the bias controls
for the remaining two colors (CCW).
f. Attach two round magnets on the picture tube screen at 3
o'clock and 9 o'clock positions, approximately one (1) inch
from the edge of the mask (use double-sided tape).
DEFLECTION YOKE
PURITY &CONVERGENCE
MAGNET ASSEMBLY
RUBBER
WEDGES
GLASS CLOTH TAPE
PURITY MAGNET
6-POLE
4-POLE
4-POLE
MAGNET
CONVERGENCE MAGNET ASSEMBLY
6-POLE
MAGNES
PURITY MAGNET(2-POLE)
X-AXIS YOKE
POSITIONING
(L/R PURITY)
6-POLE
MAGNETS
CONVERGENCE MAGNET ASSEMBLY
- 15 -
8. Referring to above, perform the following two steps:
a. Adjust the yoke Z-axis to obtain equal blue circles.
b. Adjust the appropriate beam bender tabs to obtain correct
purity (four equal circles).
9. After correct purity is set, tighten the yoke clamp screw and
remove the two screen magnets.
10. Remove the AC power and rotate the receiver 180 degrees
(facing "magnetic south").
11. Reconnect the internal degaussing coil.
12. Turn the receiver on for 10 seconds (make sure the receiver
came on) to perform internal degaussing, and then turn the
receiver off.
13. Unplug the internal degaussing coil.
14. Turn the receiver on and check the purity by holding one (1)
round magnet at the 3 o'clock and a second round magnet at
9 o'clock position. If purity is not satisfactory, repeat steps 8
through 14.
15. Turn off the receiver and reconnect the internal degaussing coil.
¯ Convergence Adjustment
Caution: This procedure DOES NOT apply to bonded yoke and
picture tube assemblies.
Do not use screen magnets during this adjustment
procedure. Use of screen magnets will cause an
incorrect display.
1. Remove AC power and disconnect the internal degaussing coil.
2. Apply AC Power and set the brightness to the Picture Reset
condition. Set the Color control to minimum.
3. Make horizontal line.
4. Adjust the Red, Green and Blue Bias controls to get a dim
white line.
5. Restore the screen by removing the horizontal line.
6. Reconnect the internal degaussing coil and apply AC power.
7. Turn the receiver on for 10 seconds to perform internal
degaussing and then turn the receiver off again.
8. Unplug the internal degaussing-coil.
9. Turn the receiver on, connect a signal generator to the VHF
antenna terminal and apply a crosshatch signal.
Caution: During the convergence adjustment procedure, be
very careful not to disturb the purity adjustment tabs.
Purity should be confirmed before proceeding with the
convergence adjustments.
Note:
Make sure the focus is set correctly on this instrument
before proceeding with the following adjustment.
10. Converge the red and blue vertical lines to the green vertical
line at the center of the screen by performing the following
steps (below TABLE).
a. Carefully rotate both tabs of the 4-pole ring magnet
simultaneously in opposite directions from the 12 o'clock
position to converge the red and blue vertical lines.
b. Carefully rotate both tabs of the 6-pole ring magnet
simultaneously in opposite directions form the 12 o'clock
position to converge the red and blue (now purple)
vertical lines with the green vertical line.
11. Converge the red and blue horizontal with the green line at
the center of the screen by performing the following steps.
(below TABLE)
a. Carefully rotate both tabs of the 4-pole ring magnet
simultaneously in the same direction (keep the spacing
between the two tabs the same) to converge the red and
blue horizontal lines.
b. Carefully rotate both tabs of the 6-pole ring magnet
simultaneously in same direction (keep the spacing between
the two tabs the same) to converge the red and blue (now
purple) horizontal lines with the green horizontal line.
c. Secure the tabs previsouly adjusted by locking them in
place with the locking tabs on the beam bender.
MAGNETS
RED RED
1.ADJUST YOKE Z-AXIS FIRST
TO GET EQUAL BLUE
COLOR CIRCLES
2 .ADJUST BEAM BENDER 2 POLE
MAGNET TO GET FOUR EQUAL
COLOR CIRCLES
PURITY & CONVERGENCE ADJUSTMENT
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