Panasonic CT-27D10B, CT-27D10UB, CT-27D10DB Service Manual

ORDER NO. MTNC000417C1
B5
Color Television
Main Manual
(NA8)
Panasonic
Models
Chassis
CT-27D10B AP338 CT-27D10UB AP338 CT-27D10DB AP338
This Service manual is issued as a service guide for the models of the NA8 family listed above. Included in this manual are a set of schematic, block diagrams, functional descriptions, alignment procedures, disassembly procedures, and a complete parts list.
The service technician is required to read and follow the “Safety Precautions” and “Important Safety Notice” in this Main Manual.
Copyright 2000 by Matsushita Electric Corporation of America. All rights reserved. Unauthorized copying
®
and distribution is a violation of law.
Important Safety Notice
Special components are used in this television set which are important for safety. These parts are identified on the
schematic diagram by the symbol and printed in BOLD TYPE on the replacement part list. It is essential that these critical parts are replaced with the manufacturer’s specified replacement part to prevent X-ray radiation,
shock, fire or other hazards. Do not modify the original design without the manufacturer’s permission.
Safety Precautions
General Guidelines
An Isolation Transformer should always be used during the servicing of a receiver whose chassis is not isolated from 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 from being damaged by accidental shorting that may occur during servicing. When servicing, observe the original lead dress, especially in the high voltage circuit. Replace all damaged parts (also parts that show signs of overheating.) Always Replace Protective Devices, such as fishpaper, isolation resistors and capacitors, and shields after servicing the Receiver. Use only manufacturer’s recommended rating for fuses, circuits breakers, etc. High potentials are present when this Receiver is operating. Operation of the Receiver without the rear cover introduces danger for electrical shock. Servicing should not be performed by anyone who is not thoroughly familiar with the necessary precautions when servicing high-voltage equipment.
Extreme care should be practiced when Handling the Picture Tube. Rough handling may cause it to implode
due to atmospheric pressure. (14.7 lbs per sq. in.). Do not nick or scratch the glass or subject it to any undue pressure. When handling, use safety goggles and heavy gloves for protection. Discharge the picture tube by shorting the anode to chassis ground (not to the cabinet or to other mounting hardware). When discharging connect cold ground (i.e. dag ground lead) to the anode with a well insulated wire or use a grounding probe. Avoid prolonged exposure at close range to unshielded areas of the picture tube to prevent exposure to X­ray radiation. The Test Picture Tube used for servicing the chassis at the bench should incorporate safety glass and magnetic shielding. The safety glass provide shielding for the tube viewing area against X-ray radiation as well as implosion. The magnetic shield limits the X-ray radiation around the bell of the picture tube in addition to the restricting magnetic effects. When using a picture tube test jig for service, ensure that the jig is capable of handling 40kV without causing X­ray radiation. Before returning a serviced receiver to the owner, the service technician must thoroughly test the unit to ensure that is completely safe to operate. Do not use a
line isolation transformer when testing.
Leakage Current Cold Check
Unplug the AC cord and connect a jumper between the two plug prongs. Measure the resistance between the jumpered AC plug and expose metallic parts such as screwheads, antenna terminals, control shafts, etc. If the exposed
metallic part has a return path to the chassis, the reading should be between 240kand 5.2MΩ. If the exposed metallic part does not have a return path to the chassis, the reading should be infinite.
Leakage Current Hot Check (Fig. 1)
Plug the AC cord directly into the AC outlet. Do not use an isolation transformer during the check. Connect a 1.5k 10 watt resistor in parallel with a
0.15µF capacitor between an exposed metallic part and ground. Use earth ground, for example a water pipe. Using a DVM with a 1000 ohms/volt sensitivity or higher, measure the AC potential across the resistor. Repeat the procedure and measure the voltage present with all other exposed metallic parts. Verify that any potential does not exceed 0.75 volt RMS. A leakage current tester (such a Simpson Model 229, Sencore Model PR57 or equivalent) may be used in the above procedure, in which case any current measure must not exceed 1/2 milliamp. If any measurement is out of the specified limits, there is a possibility of a shock hazard and the Receiver must be repaired and rechecked before it is returned to the customer.
AC VOLTMETER
COLD WATER PIPE (GROUND)
0.15µF
TO INSTRUMENT’S EXPOSED METAL PART S
1500,10 W
Figure 1. Hot Check Circuit
X-ray Radiation
WAR NING: The potential source of X-ray radiation in the
TV set is in the High Voltage section and the picture tube.
Note: It is important to use an accurate, calibrated
high voltage meter.
Set the brightness, picture, sharpness and color controls to Minimum. Measure the High Voltage. The high voltage should be 28.30kV ± 1.25kV. If the upper limit is out of tolerance, immediate service and correction is required to insure safe operation and to prevent the possibility of premature component failure.
Horizontal Oscillator Disable Circuit Test
This test must be performed as a final check before the Receiver is returned to the customer. See Horizontal Oscillator Disable Circuit Procedure Check in this manual.
- 2 -
Important Safety Notice . . . . . . . . . . . . . . . . . . 2
Safety Precautions . . . . . . . . . . . . . . . . . 2
Service Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Horizontal Oscillator Disable Circuit . . . . 5
Receivers Feature Table . . . . . . . . . . . . . . . . . . 6
Location of Controls (Receiver)
Receiver Front Control Panel . . . . . . . . . 7
Location of Controls (Remote)
EUR511502 . . . . . . . . . . . . . . . . . . . . . . 8
Service Adjustments
(Electronic Control). . . . . . . . . . . . . . . . . . 24
Sub-Brightness . . . . . . . . . . . . . . . . . . . 24
Sub-Contrast. . . . . . . . . . . . . . . . . . . . . 24
Tint/Color Adjustment . . . . . . . . . . . . . . 24
Color Temperature Adjustment . . . . . . . 25
Complete Adjustment . . . . . . . . . . . . . . 25
Horizontal Centering . . . . . . . . . . . . . . . 26
MTS Circuit Adjustment . . . . . . . . . . . . 26
Input Level Adjustment . . . . . . . . . . . . . 26
Stereo Separation Adjustment . . . . . . . 26
Clock Adjustment . . . . . . . . . . . . . . . . . 27
Vertical Size . . . . . . . . . . . . . . . . . . . . . 27
Service Adjustments
(Mechanical Controls). . . . . . . . . . . . . . . . 27
VCO Field Adjustment L105 . . . . . . . . . 27
Focus (Part of T551). . . . . . . . . . . . . . . 27
Disassembly for Service . . . . . . . . . . . . . . . . . . 9
Disassembly for CRT Replacement . . . . . . . . . 9
Chassis Service Adjustment Procedures . . . 10
131.0V B+ Voltage Confirmation . . . . . 10
Source Voltage Chart . . . . . . . . . . . . . . 10
High Voltage Check . . . . . . . . . . . . . . . 10
Purity and Convergence Procedures . . . . . . .11
Serviceman Mode (Electronic Controls) . . . . 14
Entering Serviceman Mode . . . . . . . . . 14
Toggle between Modes. . . . . . . . . . . . . 14
Exiting the Serviceman Mode . . . . . . . . 14
Sub-Data Adjustment (B) . . . . . . . . . . . 15
Cut-Off Adjustment (C) . . . . . . . . . . . . . 15
Pin Cushion Adjustment (D) . . . . . . . . . 16
MTS Adjustment (M). . . . . . . . . . . . . . . 16
PIP Adjustment (P) . . . . . . . . . . . . . . . . 17
Options Adjustment (S) . . . . . . . . . . . . 18
Comb Filter Adjustment (X) . . . . . . . . . 19
To Check Purity . . . . . . . . . . . . . . . . . . 20
Helpful Hints . . . . . . . . . . . . . . . . . . . . . 20
Instructional Flow Chart
for Serviceman Mode . . . . . . . . . . . . . . . . 21
Audio Signal Path Block Diagram . . . . . . . . . 28
Video Signal Path Block Diagram . . . . . . . . . 29
Video-Chroma Signal Path Block Diagram . . 30
IC101 VCJ IN/OUT Pins and Functions . . . . . 31
IC001 MPU IN/OUT Pins and Functions. . . . . 32
Component Identification . . . . . . . . . . . . . . . . 33
Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Schematics and Voltages
A-Board (Left Portion) . . . . . . . . . .Sheet-1A
A-Board (Right Portion) . . . . . . . . . Sheet-2A
C-Board . . . . . . . . . . . . . . . . . . . . . .Sheet-1B
Waveforms. . . . . . . . . . . . . . . . . . . .Sheet-1B
Layouts
A & C-Boards. . . . . . . . . . . . . . . . . .Sheet-1B
- 3 -
Service Notes
Note: These components are affixed with glue. Be careful not to break or damage any foil under the
component or at the pins of the ICs when removing. Usually applying heat to the component for a short time while twisting with tweezers will break the component loose.
Leadless Chip Component (surface mount)
Chip components must be replaced with identical chips due to critical foil track spacing. There are no holes in the board to mount standard transistors or diodes. Some chips capacitor or resistor board solder pads may have holes through the board, however the hole diameter limits standard resistor replacement to 1/8 watt. Standard capacitor may also be limited for the same reason. It is recommended that identical components be used. Chip resistor have a three digit numerical resistance code - 1st and 2nd significant digits and a multiplier. Example: 162 = 1600 or 1.6k resistor, 0 = 0 (jumper). Chip capacitors generally do not have the value indicated on the capacitor. The color of the component indicates the general range of the capacitance. Chip transistors are identified by a two letter code. The first letter indicates the type and the second letter, the grade of transistor. Chip diodes have a two letter identification code as per the code chart and are a dual diode pack with either common anode or common cathode. Check the parts list for correct diode number.
Component Removal
1. Use solder wick to remove solder from component end caps or terminal.
2. Without pulling up, carefully twist the component with tweezers to break the adhesive.
3. Do not reuse removed leadless or chip components since they are subject to stress fracture during removal.
Chip Component Installation
1. Put a small amount of solder on the board soldering pads.
2. Hold the chip component against the soldering pads with tweezers or with a miniature alligator clip and apply heat to the pad area with a 30 watt iron until solder flows. Do not apply heat for more than 3 seconds.
TYPE
Chip Components
GRADE
c
SOLDER CAPS
How to Replace Flat-IC
- Required Tools -
Soldering iron De-solder braids
Iron wire or small awl • Magnifier
1. Remove the solder from all of the pins of a Flat-IC by using a de-solder braid.
De-Solder
Flat-IC
2. Put the iron wire under the pins of the Flat-IC and pull it in the direction indicated while heating the pins using a soldering iron. A small awl can be used instead of the iron wire.
Iron Wire
Pull
Soldering Iron
Soldering Iron
3. Remove the solder from all the pads of the Flat-IC by using a de-solder braid.
Soldering Iron
De-Solder Braid
Flat IC
4. Position the new Flat-IC in place (apply the pins of the Flat-IC to the soldering pads where the pins need to be soldered). Properly determine the positions of the soldering pads and pins by correctly aligning the polarity symbol.
Polarity Symbol
123.........
5. Solder all pins to the soldering pads using a fine tipped soldering iron.
Braid
Awl
b
ANODES
MH DIODE
e
TRANSISTOR
COMMON CATHODE
SOLDER CAPS
CAPACITOR
1ST DIGIT
RESISTOR
2ND DIGIT
MULTIPLIER =1600 = 1.6k
Solder
Soldering Iron
6. Check with a magnifier for solder bridge between the pins or for dry joint between pins and soldering pads. To remove a solder bridge, use a de-solder braid as shown in the figure below.
De-Solder Braid
Solder Bridge
Soldering Iron
- 4 -
Service Notes (Continued)
IMPORTANT: To protect against possible damage to
the solid state devices due to arcing or static discharge, make certain that all ground wires and CTR DAG wire are securely connected.
CAUTION: The power supply circuit is above earth ground and the chassis cannot be polarized. Use an isolation transformer when servicing the Receiver to avoid damage to the test equipment or to the chassis. Connect the test equipment to the proper ground ( ) or
( ) when servicing, or incorrect voltages will be measured.
WARNING: This Receiver has been designed to meet or exceed applicable safety and X-ray radiation protection as specified by government agencies and independent testing laboratories.
To maintain original product safety design standards relative to X-ray radiation and shock and fire hazard,
parts indicated with the symbol on the schematic must be replaced with identical parts. Order parts from
the manufacturer’s parts center using the parts numbers shown in this service manual, or provide the chassis number and the part reference number.
For optimum performance and reliability, all other parts should be replaced with components of identical specification.
Procedure:
1. Tune in a station to verify that the horizontal is in sync.
2. Obtain a Monoscope pattern or a signal generator crosshatch pattern
3. Connect the voltmeter (-) lead to TPD2 and the (+) lead to TPD1 (junction of D55b anode, R556 & R557). Set Bright level to (0) and Picture for a 1.8 volt reading on the voltmeter.
4. Turn the Receiver OFF. Connect a jumper across IC803 pin 3 and pin 4. Apply +9V DC to cathode of D001.
5. Reduce the AC supply voltage to approximately 45V. Connect the high voltage meter to the CRT anode. (H.V. button).
Note: Use the Dag Ground (C10 on the CRT Board)
to connect the (-) lead of the meter.
6. Turn the Receiver ON. Slowly increase the AC supply voltage and verify that the high voltages does not exceed 37.1kV when horizontal; just begins to pull out of sync. If the high voltage is not within the specified limit, the cause must be determined and corrected before the Receiver is returned to the customer.
Horizontal Oscillator Disable Circuit
This chassis employs a special circuit to protect against excessive high voltage and beam current. If, for any reason, the high voltage and beam current exceed a predetermined level this protective circuit activates and detunes the horizontal oscillator that limits the high voltage. The over-voltage protection circuit is not adjustable. However, if components indicated by the
symbol on the schematic in either the horizontal sweep system or the over-voltage protection circuit
itself are changed, the operation of the circuit should be checked using the following procedure:
Equipment needed to check the disabled circuit:
1. Voltmeter (0 - 200V scale)
2. High Voltage Meter (0- 50kV)
3. Variac or Isolation Transformer
- 5 -
Receiver Feature Table
FEATURE\MODEL CT-27D10B/UB CT-27D10DB
Chassis NA8 NA8
Tunning system 96K 96K
# of channels 181 181
Menu language Eng/Span/Fr Eng/Span/Fr
Closed Caption XX
V-Chip XX
75 input XX
Remote Model # EUR511502 EUR511502
Picture tube M68LGL061X M68LGL061X
Black Face Regular Tube XX
Comb Filter 3 Line Digital 3 Line Digital
H. Edge Correction XX
V/A norm XX
Color Temp XX
MTS/SAP/DBX XX
BASS/BL/TRE Control XX
AI Sound XX
Surround XX
Built-in audio power 5Wx2 (10%) 5Wx2 (10%)
# of speakers 22
A/V in (rear/front) 3(2/1) 3(2/1)
S-VHS Input (rear/front) 1/0 1/0
Component Input (Y,Pb,Pr)
Audio Out (FAO: F, VAO: V)
Headphone Jack Mini plug Mini plug
Dimensions mm (WxDxH) in
Weight (kg/lbs) 35/77.2 35/77.2
Power source (V/Hz) 120/60 120/60
Anode voltage 28.30kV ± 1.25kV 28.30kV ± 1.25kV
Video input jack
Audio input jack 500mV RMS 47k 500mV RMS 47k
A-Board TNP2AH017 NIL NIL
665.2x544.5x594.8
1V
p-p
11
F, V F, V
665.2x544.5x594.8
26.2x21.5x23.5
75, phono jack 1V
26.2x21.5x23.5
75, phono jack
p-p
C-Board TNP2AA047 AP AP
Table 1. Receiver Features
Specifications are subject to change without notice or obligation. Dimensions and weights are approximate.
- 6 -
Location of Controls (Receiver)
1
4 532
Remote Control
Sensor
Front A/V Input
Figure 2. Location of Controls (Receiver).
Quick Reference Control Operation
Quick Reference
Control Operation
1
Power Button - Press to turn ON or OFF.
Volume Buttons - Press to adjust Sound Level, or to adjust Audio Menus, Video
2
Menus, and select operating features when menus are displayed
Channel Buttons - Press to select programmed channels. Press to highlight desired features when menus are displayed. Also use to select Cable Converter box channels
3
after programming Remote Control Infra-red codes (the TV/AUX/CABLE switch must be set in CABLE position).
Action Button - Press to display Main Menu and access On Screen feature and
4
Adjustment Menus.
5
TV/Video Button - Press to select TV or Video Input.
- 7 -
Location of Controls (Remote)
REMOTE CONTROL
POWER
Press to turn ON and OFF.
Presione para ENCENDER y APAGAR.
Appuyer pour établir ou couper le contact.
TV/VIDEO
Press to select TV or Video Mode.
Presione para seleccionar la Modalidad de Televisión ó Video.
Appuyer pour sélectionner le mode télé ou vidéo.
VOL
Press to adjust TV sound and navigate in menus.
Presione para ajustar el sonido de la Televisión y accesar opciones en los menús.
Appuyer pour régler le niveau sonore et se déplacer au sein des menus.
MUTE
Press to mute sound. Press to access and cancel (CC) Closed Caption.
Presione para silenciar el sonido. También presione para activar y cancelar la Modalidad de Subtítulos (CC).
Appuyer pour couper le son. Appuyer pour mettre le décodeur de sous-titres (CC) en ou hors circuit.
LIGHT
Press to light remote control buttons.
Presione para iluminar los botones del
control remoto.
Appuyer pour éclairer les touches de la
télécommande.
TV, VCR, DBS/CBL, DVD
Press to select remote operation.
Presione para seleccionar el funcionamiento del Control Remoto.
Appuyer pour sélectionner le fonctionnement télécommandé.
EXIT/GUIDE
DBS function buttons.
Botones de función DBS.
Touches de fonctions DBS.
CH
Press to select next channel and navigate in menus.
Presione para seleccionar el siguiente canal u opción en el menú.
Appuyer pour sélectionner le prochain canal et pour se déplacer au sein des menus.
ACTION
Press to access menus.
Presione para accesar los menús.
Appuyer pour accéder aux menus.
“0”~ “9”
Press numeric keypad to select any channel.
Presione el teclado numérico para seleccionar cualquier canal.
Appuyer sur une touche numérique du clavier pour sélectionner un canal.
R-TUNE
Press to switch to previously viewed channel or video mode.
Presione para regresar al canal previamente visto.
Appuyer pour revenir au canal précédemment capté.
Figure 3. Location of Controls (Remote).
EUR511502
- 8 -
RECALL
Press to display time, channel, sleep timer, and other options.
Presione para visualizar la Hora (Time), Canal (Channel), Cronómetro de Apagado Automático (Sleep Timer), y otras opciones.
Appuyer pour afficher l'heure, le numéro du canal, l'état de la minuterie-sommeil et d'autres options.
REW, PLAY, FF, TV/VCR, STOP, PAUSE, REC, VCR/DBS CHANNEL
Component function buttons.
Botones de función de los componentes.
Touches de fonctions d'appareil auxiliaire.
Disassembly for Service
Back Cover
Remove all the screws marked with an arrow( ) from the back of the Receiver.
Note: Screw configuration, type, and number of
screws vary depending on the model of the Receiver serviced and the application; various models are covered in this Manual. Use same hardware when reassembling the receiver.
3 screws at the top edge of the Receiver.
1 screw at each lower corner of the Receiver.
1 screw by the AC cord assembly.
1 screw by the A/V jacks.
1 screw by the Fly-back assembly.
A-Board - Main Chassis
1. Slide the chassis completely out of the guide rails.
2. Stand the Receiver on its edge. The underside of the board is completely accessible for component replacement.
Note: Some tie-wraps that secure the wire dressings
may need to be unfastened for chassis removal.
C-Board - CRT Output
Plugs into the socket on the CRT neck.
Speakers
Speaker is secured to the cabinet’s front with 4 screws.
Keyboard Push Button Assembly
Fastened to the inside of the cabinet front with up to 3 screws.
Disassembly for CRT Replacement
1. Discharge the CRT as instructed in the Safety Precautions (see page 2).
2. Disconnect the yoke (DY) plug, degaussing coil (DEG) plug and the CRT 2nd anode button from the main board.
3. Remove the C-Board from the CRT base and unplug the black wire (CRT dag ground) C10.
4. Disconnect the A11, A12, and Speakers plugs from the A-Board.
5. Lift the Main Chassis (A-Board) and all mounted boards completely out with the CRT Board attached.
CRT Replacement
1. Perform Disassembly for CRT Replacement procedure.
2. Insure that the CRT H.V. Anode button is discharged before handling the CRT. Read the Safety Precautions (see page 2) on handling the picture tube.
3. Remove the components from the CRT neck and place the cabinet face down on a soft pad.
4. Note the original order for the CRT mounting hardware as they are remove from the CRT mounting brackets at each corner of the CRT.
5. Remove the CRT with the degaussing coil and the dag ground braid attached.
6. Note the original locations and mounting of the degaussing coil and the dag ground assembly to insure proper reinstallation on the replacement CRT.
To remove and re-mount the degaussing coil:
The degaussing coil is held in place by clampers fastened to the CRT corner ears. These clampers must be installed onto the replacement CRT prior to mounting the degaussing coil.
To remove and re-mount the dag ground braid:
a.Unhook the coil spring from the bottom corners
of the CRT ears.
b.Release the braid loop from the upper corners of
the CRT ears.
7. Mount the dag ground braid on the replacement CRT. Position the degaussing coil with new ties. Dress coil as was on the original CRT.
8. Replace the components on CRT neck and reinstall into cabinet. Verify that all ground wires and circuit board plugs get connected.
- 9 -
Chassis Service Adjustment Procedures
All service adjustments are factory preset and should not require adjustment unless controls and/or associated components are replaced.
Note: Connect the (-) lead of the voltmeter to the appropriate ground. Use IC803’s heat sink when the HOT ground
symbol ( ) is used. Otherwise, use COLD ground ( ) — Tuner shield, IC451’s heat sink or FA2.
Figure 4. A-Board Main Components
IC451
HOT ( )
RL801
IC 803
F801
TPD8
TPD9
C552
IC 002
FA1
DATA
T
T U
U N
N E
E R
R
TP15
CLK
IC 001
IC 6501
FA2
TP
IC 101
IC 2302
IC 2361
IC 551
IC 552
IC 003
SP
COLD ( )
IC 3001
MOMENTARILY CONNECT A JUMPER FOR ENTERING SERVICE MODE (FA1 to FA2 )
131.0V B+ Voltage Confirmation
Adjust Picture Menu for normalized video adjustments.
1. Set the Bright and the Picture to Minimum by using the Picture Menu.
2. Connect the DVM between C809(+ side) and cold ground ( ).
3. Confirm that B+ voltage is 131.0V ± 2.5V. This voltage supplies B+ to the Horizontal Output & Flyback circuits.
Source Voltage Chart
120V AC line input. Set the Bright and the Picture to
High Voltage Check
1. Select an active TV channel and confirm that horizontal is in sync.
2. Adjust Brightness and Picture using Picture Icon menu so video just disappears.
3. Confirm B+ 131V is within limit.
4. Using a high voltage meter confirm that the High Voltage is 28.30kV ± 1.25kV.
Minimum by using the Picture Menu. Use cold ground ( ) for the (-) lead of the DVM.
Q 501
Q 551
D554
FOCUS SCREEN
LOCATION VOLTAGE
TPD8 27.4V ± 2V
TPD9 13.0V ± 2V
C552 (+) side 8.0V ± 1V
IC551 Pin3 9.0V ± 0.5V
D554 Cathode 220V ± 15V
C572 (+) side 5.0V ± 0.25V
- 10 -
Purity and Convergence Procedure
Adjustment is necessary only if the CRT or the deflection yoke is replaced or if the setting was disturbed. The complete procedure consists of:
1. Vertical Raster Shift Adjustment. (Only for Models
with Purity/Convergence Assembly with 4 Pairs of Rings).
2. Initial static convergence.
3. Setting the purity.
4. Final static convergence.
When the CRT or the Yoke is Replaced
Place the yoke on the CRT neck (do not tighten the clamp).
For a 2-piece assembly (see Fig. 5):
Position purity/convergence assembly as shown and tighten clamp snugly. Remove the hot-melt glue seal on assembly and position like tabs of purity device together at 12 o’clock to reduce its magnetic field effect.
R&B Convergence Rings
R&B&G Convergence Rings
G3 G4
Purity Rings Centered
Over G3/G4 Gap
For a 1-piece assembly (see Fig. 8):
Position like tabs of purity devices together at 12 o’clock to reduce any magnetic field effect. (For better results, note part number and look for specifications at Service Center)
Figure 8. Positioning of Purity/Convergence
Assembly (1-piece assembly)
For either assemblies:
Turn the Receiver ON. Operate the Receiver for 60 minutes using the first Purity Check field (white screen) to stabilize the CRT.
Fully degauss the Receiver by using an external degaussing coil.
Slide the deflection yoke back and forth on the neck of the CRT until it produces a near white, uniform raster.
Figure 5. Positioning of Purity/Convergence Assembly
(2-piece assembly)
For models using 4 pairs of rings, place the vertical raster shift tabs at 3 o’clock (90
o
from the purity and
convergence tabs, see Fig. 6 and Fig. 7)
R&B Convergence Rings
R&B&G Convergence Rings
Vertical Raster Shift Ring
G3 G4
Purity Rings Centered Over G3/G4 Gap
Figure 6. Positioning of Purity/Convergence Assembly
(4 Pairs of Rings)
R&B&G Convergence Rings
R&B Convergence Rings
Vertical Raster
Shift Rings
Purity Rings
90
o
Figure 7. Positioning of Purity/Convergence Assembly
(4 Pairs of Rings)
Vertical Raster Shift Adjustment (Only for
Models with Purity/Convergence Assembly with 4 Pairs of Rings).
Apply a green pattern with a horizontal line, adjust the Deflection Yoke so that has no tilt, then secure it. Adjust center line of the pattern with the mechanical center of the CRT, this center is determined by two marks at the side edges of the screen. To adjust the line, once the vertical raster shift tabs are place at 3 o’clock to reduce its magnetic field effect (see Fig. 6 and Fig. 7) open the tabs the same angle from the center, until the center line of the pattern becomes a straight line, centered with the marks of the CRT. (see Fig. 9)
Center line
from pattern
Mechanical
Center Marks
Vertical Raster Shift tabs
Figure 9. Ve r ti c al R as t e r S h if t Ad j u st m en t
(4 pairs of rings assembly)
Open the same angle
from center
- 11 -
Initial Center Static Convergence
Connect a dot/cross hatch generator to the Receiver and tune in a signal. Observe misconvergence at center of the screen only. Adjust the R&B pole magnets; by separating tabs and rotating to converge blue with red. Adjust the R&B and R&B&G pole magnets: by separating tabs and rotating to converge blue and red (magenta) with green.
Note: Precise convergence at this point is
not important.
Purity Adjustment
When the Receiver is in the Serviceman Mode for making electronic adjustments, press the Recall button on the Remote Control to enter Purity Check. (See the
Service Adjustments Electronic Controls
procedure). Operate the Receiver for 60 minutes using the first Purity Check field (white screen) to stabilize the CRT. Fully degauss the Receiver by using an external degaussing coil. Press the Recall button on the Remote Control again until the Purity Check (green screen) appears.
For a 2-piece assembly (see Fig. 5): Loosen the deflection yoke clamp screw and move the deflection yoke back as close to the purity magnet
as possible. Adjust the Purity rings to set the vertical green raster precisely at the center of the screen (see Fig. 10).
NOTES:
1. CRT warm up with white screen (three guns activated) is needed to stabilize the shadow mask expansion.
2. Initial center static convergence (roughly centers three gun beams) is required in order to perform purity adjustment.
Figure 10. Green Raster Adjustment
Slowly move the deflection yoke forward until the best overall green screen is displayed.
For a 1-piece assembly (see Fig. 8): Slowly move the deflection yoke and purity rings
assembly toward the CRT board and adjust the purity magnet rings to set vertical green raster at center of screen (see Fig. 10). Gradually move the deflection yoke & purity rings forward and adjust for best overall green screen.
Continue from here for either assemblies:
Tighten the deflection yoke clamp screw. Press the Recall button on the Remote Control again until the purity check (blue screen) and (red screen) appear and observe that good purity is obtained on each respective field. Press the Recall button on the Remote Control again until Purity check (white screen) appears. Observe the screen for uniform white. If purity has not been achieved, repeat the above procedure.
Green Raster
Final Convergence Procedure (see Fig. 11
through Fig. 13):
Note: Vertical size and focus adjustments must be completed prior to performing the convergence adjustment. Connect a dot pattern generator to the Receiver. The Brightness level should not be higher than necessary to obtain a clear pattern.
Converge the red and the blue dots at the center of the screen by rotating the R&B pole Static Convergence Magnets. Align The converged red/blue dots with the green dots at the center of the screen by rotating the R&B&G pole Static Convergence Magnets. Melt wax with soldering iron to reseal the magnets. Slightly tilt vertically and horizontally (do not rotate) the deflection yoke to obtain a good overall convergence. If convergence is not reached at the edges, insert permalloy (see following section) from the DY corners to achieve proper convergence. Recheck for purity and readjust if necessary. After vertical adjustment of the yoke, insert wedge at 11 o’clock position, then make the horizontal tilt adjustment. Secure the deflection yoke by inserting two side wedges at 3 and 7 o’clock positions. Apply adhesive between tab (thin portion) of wedge and CRT and place tape over the tab to secure to the CRT.
Permalloy Convergence Corrector Strip (Part No. 0FMK014ZZ)
This strip is used in some sets to match the yoke and CRT for optimum convergence. If the yoke or CRT is replaced, the strip may not be required. First converge the set without the strip and observe the corners.
If correction is needed:
1. Place strip between CRT and yoke, in quadrant needing correction. Slowly move it around for desired results.
2. Press adhesive tightly to the CRT and secure with tape.
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As the yoke is tilted
RGB
Figure 11. Vertical Yoke Movement
vertically, the rasters produced by the outside guns rotate in opposite directions.
RGB
As the yoke is tilted horizontally, one raster gets larger while the other gets smaller
Figure 12. Horizontal Yoke Movement
Raster produced from one of the outside electron beams
Raster from the other side electron beam
Static convergence magnets are set for center convergence
Static Convergence Magnets
Converges R/B with G
Purity/Convergence
Assembly Clamp
Purity Rings Adj. on
Green Raster
11 o’clock Position
Converges
R with B
Double sided adhesive tape
3 o’clock Position
Yoke Positioning Wedges for Dynamic Convergence
7 o’clock Position
Figure 13. Convergence Magnets and Wedges Location
Note: For models using 4 pairs of rings
assemblies see Fig. 6 for details
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Serviceman Mode (Electronic Controls)
This Receiver has electronic technology using the I²C Bus Concept. It performs as a control function and it replaces many mechanical controls. Instead of adjusting mechanical controls individually, many of the control functions are now performed by using “On Screen Display Menu”. (The Serviceman Adjustment Mode.)
Note: It is suggested that the technician reads all the way through and understand the following procedure for
Entering/Exiting the Serviceman Adjustment Mode; then proceed with the instructions working with the Receiver. When becoming familiar with the procedure, the Flow Chart for Serviceman Mode may be used as a quick guide.
Quick Entry to Serviceman Mode:
At times when minor adjustments need to be done to the electronic controls, the method of Entering the serviceman Mode without removal of the cabinet back is as follows using the Remote Control:
1. Select SET-UP icon and select CABLE mode.
2. Select TIMER icon and set SLEEP time for 30 Min.
3. Press ACTION button 3 times to exit menus.
4. Tune to the Channel 124.
5. Adjust VOLUME to minimum (0).
6. Press the VOL button (decrease) on Receiver. Red “CHK” appears in upper corner.
To toggle between Aging and Serviceman modes:
While the “CHK” is displayed on the left top corner of the CRT, pressing the Action and the Volume Up buttons on the Receiver simultaneously will toggle between the modes. Red “CHK” for Serviceman and yellow “CHK” for Aging.
7. Press the Power Button on the Remote Control to select one of seven Serviceman Adjustment Modes.
1) B= Serviceman VCJ SUB-DATA ADJUSTEMENT.
2) C= Serviceman VCJ CUT-OFF ADJUSTMENT.
3) D= Serviceman PIN CUSHION ADJUSTMENT.
4) M= Serviceman MTS ADJUSTMENTS.
5) P= Serviceman PIP ADJUSTMENT. (Models with PIP only)
6) S= Serviceman OPTIONS ADJUSTMENTS.
7) X = Serviceman COMB FILTER ADJUSTMENT.
8) “CHK” = Normal operation of CHANNEL and VOLUME .
Note: Only the applicable settings for
the Receiver serviced will be available (See a in Fig. 14).
b
32 B 0 2 215 C 0
An address Menu appears in the right hand corner of the screen
Figure 14. Serviceman Mode Menu Adjustments.
a
b
a
Exiting the Serviceman Mode:
Press the Action and the Power buttons on the Receiver simultaneously for at least 2 seconds. THE RECEIVER EXITS SERVICEMAN MODE.
The Receiver momentarily shuts off; then comes back on tuned to channel 3 with a preset level of sound. Any programmed channels, channels caption data and some others user defined settings will be erased.
IMPORTANT NOTE: Always Exit the Serviceman Mode Following Adjustments.
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Press the Power Button on the Remote Control to select the Serviceman Adjustment .
For Adjustments:
1.Press Channel Up/Down on the Remote Control to select one of
the available Service Adjustments (a in Fig. 14).
Note: Write Down the original
value set (b in Fig. 14) for each address before modifying anything. It is easy to erroneously adjust the wrong item.
2.Press Volume Up/Down on the Remote Control to adjust the
level of the selected Service Adjustment (b in Fig. 14).
CH
Sub-Data Adjustment
B0 SUB-COLOR 31
B1 SUB-TINT 31
B2 SUB-BRIGHTNESS 31
B3 SUB-CONTRAST 16
B4 SUB-TINT VIDEO 16
B5 SUB-COLOR VIDEO 16
B6 SUB-TINT COMP 63
B7 SUB-COLOR COMP 31
B8 SUB SHARP TV/VIDEO 10
B9 SUB SHARP S-VHS/COMP 31
BA SUB-CONTRAST FIXED 15
Cut-Off Adjustment
Default
Level
Default
Level
CH
CH
PW
CH
IMPORTANT NOTE:
Always Exit the Serviceman Mode Following Adjustments.
C0 CUT-OFF R 128
C1 CUT-OFF G 128
C2 CUT-OFF B 128
C3 USER BRIGHTNESS 31
C4 G DRIVE 64
C5 B DRIVE 64
C6 DRIVE C TEMP 8
C7 CONTRAST C TEMP 5
PW
To D Items.
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