7. Electrical Diagram’s en PWB’sDiagram PWB
Large Signal Panel(Section 1)2124-29
Large Signal Panel(Section 2)2224-29
Large Signal Panel(Section 3)2324-29
CRT Red3033
CRT Blue3133
CRT Green3233
Small Signal Board(Section 1)3445-50
Small Signal Board(Section 2)3545-50
Small Signal Board(Section 3)3645-50
Small Signal Board(Section 4)3745-50
Small Signal Board(Section 5)3845-50
Small Signal Board(Section 6)3945-50
Small Signal Board(Section 7)4045-50
Small Signal Board(Section 8)4145-50
Small Signal Board(Section 9)4245-50
Small Signal Board(Section 10) 4345-50
Small Signal Board(Section 11) 4445-50
Side jack panel5152
Analog SSB:IF-Video-Sync-Chroma (Diagr. C1) 5359-60
Analog SSB: Video Features(Diagram C2) 5459-60
Copyright 2001 Philips Consumer Electronics B.V. Eindhoven, The Netherlands.
All rights reserved. No part of this publication may be reproduced, stored in a
retrieval system or transmitted, in any form or by any means, electronic, mechanical,
photocopying, or otherwise without the prior permission of Philips.
Analog SSB: Micro Controller(Diagram C3) 5559-60
Analog SSB: Memory(Diagram C4) 5659-60
Analog SSB: Audio Processing(Diagram C5) 5759-60
Analog SSB: Audio Processing(Diagram C6) 5859-60
Analog SSB: SSB Connector(Diagram C7) 5959-60
Double Window: PIP(Diagram F1) 6166-67
Double Window: Tuner(Diagram F2) 6266-67
Double Window: I/O Processing (Diagram F3) 6366-67
Double Window: IF-Video-Sync(Diagram F4) 6466-67
Double Window: V-Chip Processor(Diagram F5) 6566-67
Double Window: NV-ROM(Diagram F6) 6566-67
PFC Filter Panel6869
SVM Panel7071
Center Channel Switch(Diagram K) 7272
AC Power Switch(Diagram L) 7373
Local Control7475
IR-LED (Keyboard)7677
8. Alignments79
9. Circuit Description and 83
List of Abbreviations99
10 Spare Parts List101
Published by TA 0167 Service PaCEPrinted in the NetherlandsSubject to modification
3122 785 11241
Page 2
GB 2A10PTV2.0 NTSC1.
Technical Specifications, Connections, and Chassis Overview
1.Technical Specifications, Connections, and Chassis Overview
1.1Technical Specifications
Mains Voltage: 90 V - 276 V
Power Consumption: 260 W max
Standby consumption: < 3 W
Mains Frequency: 50 / 60 Hz (+/- 5%)
Tuning System: PLL
Reception: NTSC M,
1 - Video 1 Vpp / 75 ohm
2 - Audio Left (0.2 Vrms / 10 k ohm)
3 - Audio Right (0.2 Vrms / 10 k ohm)
4 - Headphone 32 - 2000 ohm / 10 mW
1.2.2Rear Connections
AV1 In
1 - Video 1 Vpp / 75 ohm
2 - Audio L (0.5 Vrms / 10 k ohm)
3 - Audio R (0.5 Vrms / 10 k ohm)
4 - Y 0.7 Vpp / 75 ohm
5 - Pb 0.7 Vpp / 75 ohm
6 - Pr 0.7 Vpp / 75 ohm
AV2 In
1 - Video 1 Vpp / 75 ohm
2 - Audio L (0.5 Vrms / 10 k ohm)
3 - Audio R (0.5 Vrms / 10 k ohm)
Page 3
Technical Specifications, Connections, and Chassis Overview
Side J
Blue CR
C P
1.3Chassis Overview
ack
Side J
Panel
Center
Channel
Switch
Red CRT
Green CRT
SVM Panel
Blue CR
Keyboard &
IR LED Panel
GB 3A10PTV2.0 NTSC1.
AC P
ower
T
Switch Panel
PIP Panel
SSB Module
SSM Panel
LSB Panel
Figure 1-2
Filter Panel
CL 16532050_001.eps
090501
Page 4
GB 4A10PTV2.0 NTSC2.
Safety Instructions, Warnings and Notes
2.Safety Instructions, Warnings and Notes
2.1Safety Instructions for Repairs
•Safety regulations require that during a repair:
– The set should be connected to the mains via an
isolating transformer;
– Safety components, indicated by the symbol
should be replaced by components identical to the
original ones;
– When replacing the CRT, safety goggles must be
worn.
•Safety regulations require that after a repair the set must
be returned in its original condition. In particular attention
should be paid to the following points.
– General repair instruction: As a strict precaution, we
advise you to resolder the solder joints through which
the horizontal deflection current is flowing, in
particular
a. All pins of the line output transformer (LOT);
b. Fly-back capacitor(s);
c. S-correction capacitor(s);
d. Line output transistor;
e. Pins of the connector with wires to the deflection
coil;
f. Other components through which the deflection
current flows.
Note: This resoldering is advised to prevent bad
connections due to metal fatigue in solder joints
and is therefore only necessary for television
sets older than 2 years.
– The wire trees and EHT cable should be routed
correctly and fixed with the mounted cable clamps.
– The insulation of the mains lead should be checked
for external damage.
– The mains lead strain relief should be checked for its
function in order to avoid touching the CRT, hot
components or heat sinks.
– The electrical DC resistance between the mains plug
and the secondary side should be checked (only for
sets which have a mains isolated power supply). This
check can be done as follows:
1. Unplug the mains cord and connect a wire
between the two pins of the mains plug;
2. Set the mains switch to the "on" position (keep
the mains cord unplugged!);
3. Measure the resistance value between the pins
of the mains plug and the metal shielding of the
tuner or the aerial connection on the set. The
reading should be between 4.5 M9 and 12 M9
4. Switch off the TV and remove the wire between
the two pins of the mains plug.
– The cabinet should be checked for defects to avoid
touching of any inner parts by the customer.
2.2Maintenance Instruction
It is recommended to have a maintenance inspection carried
out by a qualified service employee. The interval depends on
the usage conditions:
,
•When the set is used under normal circumstances, for
example in a living room, the recommended interval is 3
to 5 years.
•When the set is used in circumstances with higher dust,
grease or moisture levels, for example in a kitchen, the
recommended interval is 1 year.
•The maintenance inspection contains the following
actions:
– Execute the above mentioned 'general repair
instruction'.
– Clean the power supply and deflection circuitry on
the chassis.
– Clean the picture tube panel and the neck of the
picture tube.
2.3Warnings
•ESD
•Available ESD protection equipment:
•Be careful during measurements in the high-voltage
•Never replace modules or other components while the
•When making settings, use plastic rather than metal
All ICs and many other semiconductors are susceptible
to electrostatic discharges (ESD). Careless handling
during repair can reduce life drastically. When repairing,
make sure that you are connected with the same
potential as the mass of the set by a wristband with
resistance. Keep components and tools also at this same
potential.
– Complete kit ESD3 (small table mat, Wristband,
Connection box, Extension cable and Earth cable)
4822 310 10671
– Wristband tester 4822 344 13999
section and on the picture tubes.
unit is switched on.
tools. This will prevent any short circuits and the danger
of a circuit becoming unstable.
2.4Notes
•The direct voltages and oscillograms should be
measured with regard to the tuner earth (
) as this is called.
(
•The direct voltages and oscillograms shown in the
diagrams are indicative and should be measured in the
Service Default Mode (see chapter 5) with a colour bar
signal and stereo sound (L: 3 kHz, R: 1 kHz unless stated
otherwise) and picture carrier at 475.25 MHz.
•Where necessary, the oscillograms and direct voltages
are measured with (
Voltages in the power supply section are measured both
for normal operation (
values are indicated by means of the appropriate
symbols.
•The picture tubes PWB have printed spark gaps. Each
spark gap is connected between an electrode of the
picture tube and the Aquadag coating.
•The semiconductors indicated in the circuit diagram and
in the parts lists are completely interchangeable per
position with the semiconductors in the unit, irrespective
of the type indication on these semiconductors.
) and without aerial signal ().
) and in standby (). These
), or hot earth
Page 5
3.Directions for Use
PHILIPS
4.Mechanical Instructions
4.1Disassembly Procedures
All numbers found in the following text refer to the
CABINET DISASSEMBLY EXPLODED VIEW drawing and
apply to all models.
NOTE: If you are only servicing a PCB or speaker, you do not
have to remove the plastic upper back cover.
CABINET DISASSEMBLY EXPLODED VIEW
J
Directions for Use
GB 5A10PTV2.0 NTSC3.
PHILIPS
16
22
!
27
Optical Assembly
GG
E
H
E
4.1.1Removal of Upper Back Cover (2)
1. Remove 8 screws (A).
2. Remove 3 screws (B).
3. Lift cover up to dislodge from pegs (J) and remove cover.
4.1.2Removal of Lower Center Back Cover (1)
1. Remove 3 screws (B).
2. Remove 8 screws (C).
4.1.3Removal of Mirror Mounting Board (18)
1. Remove 6 screws (D) located in the mirror mounting
board and remove the board.
NOTE: Care should be taken NOT to place fingerprints or
smudges on mirror.
4.1.4Removal of Plastic Light Barrier (16)
1. Remove two screws (E) located at the sides of the Plastic
Light Barrier.
18
A
Right
3
Left
D
B
C
F
1
6
F
A
30
2
CL 06532143_003.eps
011100
Figure 4-1
4.1.5Removal of Side Back Covers (3)
NOTE: To gain access to the Side Jack Panel (D) and two
Speakers, remove the Left Side Back Cover.
To gain access to the AC Power Switch Panel (L), remove
the Right Side Back Cover.
1. Remove 4 screws (F) from each of the Side Back Covers.
4.1.6Removal of Large Signal Panel (A)
1. Pull 3 tabs on right of bracket and 2 tabs on left of
bracket.
2. Lift Large Signal Board up and out.
4.1.7Removal of PFC Filter Panel (G)
1. Remove 4 screws from CBA.
2. Lift PFC Filter Panel up and out.
4.1.8Removal of Small Signal Panel (C)
1. Remove 2 screws from the middle of the CBA.
2. Pull 3 tabs on right of bracket.
Page 6
GB 6A10PTV2.0 NTSC4.
3. Lift Small Signal Board up, then to the right to remove.
4.1.9Removal of Side Jack Panel (22) (D)
1. Remove Left Side Back Cover.
2. Pull tabs in; press Side Jack Panel out.
3. Remove two screws from panel.
4. Slide Side Jack Panel CBA out of bracket.
4.1.10 Removal of AC Power Switch Panel (L)
1. Remove Front Baffle (30) by gently pulling baffle frame
away from cabinet.
2. Remove Right Side Back Cover.
3. Remove 2 screws from panel.
4. Remove 2 plugs 1000 & 1002.
5. Pull panel out front of set.
4.1.11 Removal of Center Channel Switch Panel (K)
1. Remove 3 screws from panel.
4.1.12 Removal of Double Window PIP Panel (F)
1. Remove 3 screws from panel.
Mechanical Instructions
4.1.13 Removal of Analog SSB (E)
1. Pull frame up.
2. Pull board to right and then up.
4.1.14 Removal of Front Control
1. Remove front speaker baffle (30) by gently pulling baffle
frame away from cabinet.
2. Remove 3 screws from front control.
4.1.15 Removal of Euro SVM Panel (J)
1. Press 3 treelocks to remove Euro SVM board.
4.1.16 Removal of Complete Optical Assembly or Individual
Light Box Assemblies.
1. Remove the Plastic Light Barrier (16).
2. Separate CRT CBA's from assemblies to be removed.
3. To remove the complete Optical Assembly, loosen 4
screws (G) located in the assembly, and lift assembly up
and out.
4. To remove individual Light Box assemblies, loosen 4
screws (H) located in the assembly you wish to remove
and lift assembly up and out.
Page 7
Fault Finding and Repair Tips
5.Fault Finding and Repair Tips
GB 7A10PTV2.0 NTSC5.
The lowing topics are covered:
•Test points
•Service Modes
•Error code buffer and error codes
•The “blinking LED” procedure
•Trouble shooting tips
•Customer Service Mode
5.1Test Points
The A10 PTV chassis is equipped with test points shown on
the schematic diagrams.
Each test point has a reference number indicating the
schematic diagram on which it is located.
•A F106, A I126, etc.: Test points for the Large Signal
Panel [A1 - A3]
•C F001, C I001, etc.: Test points for the Small Signal
Panel [C1 - C11]
•G F114, G I001, etc.: Test points for the PFC Filter Panel
[G]
•J F004, J F006, etc: Testpoints for the SVM Panel [J]
•K I001, K I002: Test points for the Center Channel Switch
[K]
•M I004, M I005: Test points for the Local Control [M]
Measurements should be performed under the following
conditions:
Video: color bar signal
Audio: 3kHz left, 1kHz right
Note:The measurements at the following test points were
taken using a 100:1 probe:
•A I142
•A I220
5.2Service Default Mode (SDM)
5.2.1Introduction
The Service Default Mode (SDM) is a technical aid for the
service technician. The Service Default Mode (SDM)
establishes fixed, repeatable settings of customer controls,
which allow consistent measurements to be made. The SDM
also initiates the blinking LED procedure and, if necessary,
overrides the 5V protection. This mode also allows the
operating hours, the software version and error codes to be
read.
5.2.2Entering Service Default Mode
To enter the Service Default Mode, press the following key
sequence on the remote control transmitter:
0-6-2-5-9-6-MENU
Do not allow the display to time out between entries while
keying the sequence.
Upon entry into the Service Default Mode, the letters “SDM”
will be displayed at the upper right corner of the screen.
Side Jack
Panel
Center
Channel
Switch
PIP Panel
SSB Module
Red CRT
SSM Panel
Green CRT
SVM Panel
LSB Panel
Blue CRT
Keyboard &
IR LED Panel
Figure 5-1
5.2.3Special SDM Functions
Access to Normal User Menu
Pressing the “MENU” button on the remote control switches
between the SDM and the normal user menus (with the SDM
mode still active in the background)
Run Timer, Software Identification, and Error Buffer
Press the Index or status button on the remote control to
toggle the OSD (except “SDM”) ON and OFF to prevent the
OSD from interfering with measurements and oscilloscope
waveforms.
Access to SAM
To access the Service Alignment Mode while in the SDM
press the “VOLUME +” and “VOLUME -“ buttons on the local
keyboard simultaneously for at least 4 seconds.
5.2.4Exiting Service Default Mode
Filter Panel
CL 16532050_001.eps
AC Power
Switch Panel
090501
The SDM Places the Set in the Following Pre-defined
Conditions:
•Tuning frequency set to channel 3.
•Volume level set to 25% (of the maximum volume level).
•Other picture and sound settings set to 50% (mid-range).
The Following Functions are Turned Off in SDM (and
After Leaving SDM):
•Timer
•Sleep timer
The Following Functions are Disabled During SDM (and
Enabled After Leaving SDM):
•Parental lock
All other controls operate normally.
To exit the Service Default Mode, press the Power button.
Page 8
GB 8A10PTV2.0 NTSC5.
Fault Finding and Repair Tips
5.3Service Alignment Mode (SAM)
5.3.1 Introduction
The Service Alignment Mode (SAM) is used to align the set
and/or adjust the option settings and to display/clear the error
code buffer values.
Entering Service Alignment Mode
To enter the Service Alignment Mode (SAM), press the
following key sequence on the remote control transmitter:
0-6-2-5-9-6-INDEX or status.
Do not allow the display to time out between entries while
keying the sequence
It is also possible to enter the Service Alignment Mode by
pressing the “VOLUME +” and “VOLUME -” key on the local
keyboard simultaneously for at least 4 seconds when the set
is in SDM.
5.3.2Exit SAM:
To exit the Service Alignment Mode, press the Power button.
In SAM the following information is displayed on the screen:
Figure 5-2
5.3.3Explanation Notes/References:
1. Operation Hours (Run Timer):
•This display indicates the accumulated total of
operational hours. (Shown in hexadecimal format)
2. Software identification of the main micro controller
(A101US1-2.06)
•A10 is the engineering chassis name for the A10
PTV chassis
•1US1 is a character combination to indicate the
software type and the supported languages: 3AP1 or
3AP2 are also possible in the Asian Pacific Region.
•US = United States, AP = Asia Pacific
•1 = Main Software language version number
•2.06 = sub-version number
3. Error buffer (7 errors possible):
•Displays the 7 most recent errors. The most recent
error is displayed at the upper left.
4. Option bytes (8 codes possible):
•Summary of options is explained below.
5. Sub menus are listed in a scroll menu.
5.3.4 SAM Menu Control
Menu items may be selected using the cursor UP/DOWN
keys.
•The selected item will be highlighted.
• When not all menu items will fit on the screen, pressing
the cursor UP/DOWN keys on the remote transmitter will
display the next/previous menu items.
CL 16532052_003.eps
090501
With the cursor LEFT/RIGHT keys, it is possible to:
•(de)activate the selected menu item (e.g. GEOMETRY)
•change the value of the selected menu item ( e.g. VERSLOPE )
•activate the selected submenu (e.g. SERV-BLK)
Access to Normal User Menu
Pressing the “MENU” button on the remote control switches
between the SAM and the normal user menus (with the SAM
mode still active in the background). Pressing the “MENU”
key in a submenu will return the screen to the previous menu.
5.4The Menus and Submenus
5.4.1Clear Errors
Erases the contents of the error buffer. Select the CLEAR
ERRORS menu item and press the cursor LEFT or cursor
RIGHT key. The contents of the error buffer are cleared.
The functionality of the OPTIONS and ALIGNMENTS
(TUNER, WHITE TONE, GEOMETRY, SOUND, and
SMART SETTING) submenus are described in the service
adjustments.
5.4.2Error Code Buffer and Error Codes
Explanation of the Error Code Buffer
The error code buffer contains all errors detected since the
last time the buffer was erased. The buffer is written from left
to right. When an error occurs that is not yet in the error code
buffer, the error code will appear at the left side and all other
errors shift one position to the right.
The error code buffer will be cleared in the following cases:
•by activating CLEAR ERRORS in SAM menu
•exiting SDM or SAM with the “Standby" command on the
remote control
•upon automatic reset when content has not changed for
50 consecutive hours
By leaving SDM or SAM via the power switch, the error buffer
will not be reset.
Examples:
ERROR: 0 0 0 0 0 0 0 :No errors detected
ERROR: 6 0 0 0 0 0 0 :Error code 6 is the last and only
detected error
ERROR: 9 6 0 0 0 0 0 :Error code 6 was first detected and
error code 9 is the last detected (newest) error
The contents of the error buffer can also be displayed by use
of the “blinking LED” procedure, if no picture is available. See
explanation of “The blinking LED procedure “below.
5.4.3Error Code Definition
In case of non-intermittent faults, clear the error buffer before
starting the repair, to make sure “old” error codes are not
present. If possible check the entire content of the error
buffers. In some situations an error code is only the result of
another error code (and not the actual cause).
Note: a fault in the protection detection circuitry can also lead
to a protection.
Error codes 1,2, 3, and 4 are protection codes, and in this
case the supplies of some circuits will be switched off. Also
in protection, the LED will blink the number of times
equivalent to the most recent error code.
Page 9
Fault Finding and Repair Tips
GB 9A10PTV2.0 NTSC5.
5.4.4 Error Code Table
Code Number Error Description
00Not an Error
01Too high I-beam or East/West protection
02Vertical protection
03X-Ray protection
045 volt protection
05- not used
06General IIC error
07BC loop not stabilised
08Bocma TDA888X IIC error
09Bocma IC 8v failure
10NVM IIC communication error
11Wrong NVM type
12Microp internal RAM error
13Main tuner IIC failure
14Sound IC failure
15SRAM test failure
16PIP Tuner IIC failure
17ECO Pip IC or DW Pip IC failure
18I/O expander I2C error
19Gemstar Guide Plus board
20V-chip located on the DW Pip
21Non-Volatile clock
22Incredible picture (YUV) CR
23Bocma DoubleWindow TDA888X error
24- not used
25- not used
26- not used
27Virtual Dolby
28- not used
29- not used
30CSP i2c error
31CSP NVM i2c error
32CSP NVM error - not valid data
33CSP dac i2c error
5.4.5A10 PTV Model Listing & Software
ModelSoftware
43PP925/613AP2
43PP925/973AP1
55PP925/613AP2
55PP925/973AP1
Error buffer: 12 9 6 0 0
•After entering SDM:
•The sequence will begin with 1 long blink of 750
mSeconds, then pause 1500 mSeconds, then blink twice
(indicating error code 12), then the LED will pause for 3
seconds, then blink 9 times (indicating error code 9), then
the LED will pause for 3 seconds, then blink 6 times
(indicating error code 6), then pause 3 seconds and blink
for 3 seconds again, ending the blinking sequence.
NOTE: If errors 1, 2, 3, or 4 occur the LED ALWAYS
blinks indicating the last error which occurred, even if
the set is NOT in service mode.
5.6Customer Service Mode
All A10 PTV sets are equipped with the “Customer Service
Mode” (CSM). CSM is a special service mode that can be
activated and deactivated by the customer, by request of the
service technician/dealer in order to identify the status of the
set. This CSM is a 'read only' mode, therefore modifications
in this mode are not possible.
5.6.1Entering the Customer Service Mode.
The Customer Service Mode can be switched on:
•By pressing the MUTE button on the remote control and
any key on the local keyboard (Channel Up, Channel
Down, VOL +, VOL -) on the TV simultaneously for at
least 4 seconds.
When the CSM is activated:
•picture and sound settings are set to nominal levels
•Modes that interfere with the behavior of the set are
switched off (sleep timer, auto standby, etc.)
5.6.2Exit the Customer Service Mode.
The Customer Service Mode will be switched off after:
•Pressing any key on the remote control (except “Channel
Up” or “Channel Down”)
•Switching off the TV set by pressing the Power button on
the remote control or the local keyboard.
Exiting CSM resets the TV set back to its initial values.
5.6.3The Customer Service Mode information screen
Upon entry into the Customer Service Mode the following
screen will appear.
5.5The Blinking LED Procedure
The contents of the error buffer can also be made visible
through the “blinking LED” procedure. This is especially
useful when there is no picture.
•When the SDM is entered, the LED will blink the number
of times equal to the value of the error code. Upon entry
into the SDM, the LED will blink the contents of the errorbuffer. Error-codes greater than/equal to 10 are shown in
the following manner: A long blink of 750 mSeconds
indicating the decimal digit, followed by a pause of 1500
mSeconds. The LED will then blink the number equal to
the error code. When all error-codes are displayed, the
sequence is finished with an LED display of 3 seconds.
At this point the sequence will begin again.
Example:
Error code position 1 2 3 4 5
CL 16532052_002.eps
Figure 5-3
The Customer Service Menu shows the following
information:
090501
Page 10
GB 10A10PTV2.0 NTSC5.
Fault Finding and Repair Tips
Line 1 : “HRS : nnnnn” and SWID : “A102BBC-X.YY”
HRS:
Indicates the accumulated total of operational hours. (Shown
in hexadecimal format.) (Standby hours are not counted as
operating hours).
SWID:
Software identification of the main micro controller (A10US1-
2.7)
A10 is the chassis name for the A10 PTV
•1US1 is a character combination to indicate the software
type and the supported languages: 3AP1 or 3AP2 are
also possible for the Asian Pacific Region.
•US = USA/NAFTA, AP = Asia Pacific region
•1 = Main Software language version number
•2.7 = sub-version number
Line 2 : “CODES : xx xx xx xx xx xx xx ”
Error code buffer (see explanation of error codes above)
Displays the last 7 errors of the error code buffer.
Line 3 : “OPT xxx xxx xxx xxx xxx xxx xxx xxx”
Option bytes
Option bits control the software and hardware functionality of
the A10.0. An option byte or option number represents 8 of
those bits. Each option number is displayed as a number
between 0 and 255. The set may not work correctly when an
incorrect option code is set. See Service Adjustments for
more information on correct option settings
4. Set to “ADD” with the left/right cursor keys
Line 9 : “HOTELMODE ON”
Indicates that the Hotel mode has been activated.
Line 10 : “SOURCE :”
Indicates which SOURCE is installed for this preset.
EXT1, SVHS2, EXT2, Tuner
Line 11 : “SOUND”
Indicates which sound mode is installed for this preset.
Mono, NICAM, Stereo, L1, L2, SAP, Virtual or Digital
Line 12 : “VOLUME”
Value indicates level at CSM entry.
Line 13 : “BALANCE”
Value indicates level at CSM entry.
Line 14 : “HUE”
Value indicates level at CSM entry.
Line 15 : “COLOUR”
Value indicates level at CSM entry.
Line 16 : “BRIGHTNESS”
Value indicates level at CSM entry.
Line 17 : “CONTRAST”
Value indicates level at CSM entry.
Line 4: NOT USED
Line 5 : “NO SIGNAL”
Indicates that the set is not receiving an “ident” signal on the
selected source.
•no or bad antenna signal; connect a proper antenna
signal
•antenna not connected; connect the antenna
•no channel / preset is stored at this program number; go
to the INSTALL menu and store a proper channel at this
program number
•the tuner is faulty (in this case the CODES line will
contain number 13 or 16); check the tuner and replace/
repair if necessary
Note: On some models (if the BM option is ON), BLUE
MUTE is displayed when no signal is received.
Line 6 : “TIMER ON ”
Indicates that the on/off timer is running.
The following Complaints may be caused by the activation of
the sleep timer:
The set may turn on from standby or may switch to a different
channel without using either the remote control or the local
keyboard.
To switch off the activation timer:
Select “TIMER” in the “FEATURE” menu.
Select “ACTIVATE” in the “TIMER” menu.
Set to “OFF” with the left/right cursor keys.
Line 7 : NOT AVAILABLE
Line 8 : “NOT PREFERED”
Indicates that at least one channel is deleted as a preferred
channel (by default, all channels are skipped).
Note that “SKIPPED” will always be displayed in CSM
unless all the channels are not skipped.
To add a channel as a selected channel to the list of preferred
channels:
1. Select “INSTALL” menu
2. Select “CHANNEL EDIT”
3. Select “ADD/DELETE”
Line 18: “SPEAKERS”
Indicates the speakers are “ON” or “OFF”.
Page 11
5.6.4CSM Flow Chart
y
p
Fault Finding and Repair Tips
Normal operation mode
Press "MUTE" button (RC) and
key on the local keyboard
an
(except "POWER") for more than 4 seconds
Store current picture, sound and
feature settings (for later retrieval)
Set pre-defined picture, sound and
feature settings
Ignore service unfriendly options
GB 11A10PTV2.0 NTSC5.
"Channel up"
(RC or local
keyboard)
Exit CSM
Restore picture, sound and
a
n
a
stored during entry)
Display CSM information screen
POWER
(RC or local
Other key
Figure 5-4
keyboard)
"Channel down"
(RC or local
keyboard)
Off (Exit CSM):
when the set is switched on,
icture, sound and feature
settings (that were stored
during entry) are restored
To next CSM pageTo previous CSM page
CL 06532143_007.eps
011100
Page 12
GB 12A10PTV2.0 NTSC5.
Fault Finding and Repair Tips
5.7Trouble Shooting Tips
5.7.1 The Power Supply Circuit:
When the set is turned On,the Main Switch Mode power
supply is turned On This supply produces the +130 volt,+32
volt,-32 volt,two +15 volt,and Audio supplies. When IC 7302
develops a normal steady state operation,the 130 volt supply
is sampled by resistors 3324,3323,and 3322.
This sample voltage is then sent to Shunt regulator 7303
which drives the feedback optoisolator 7303.The feedback
voltage on Pin 14 is then compared with an internal 2.5 volt
reference by comparator "C". Comparator "C"then sets the
reference voltage on the inverting side of comparator "B"to
control the On time of the drive at Pin 3.If the voltage on Pin
14 increases due to the 130 volt supply increasing,the On
time of the pulse on Pin 3 will be reduced.If the 130 volt
supply decreases,the voltage on Pin 14 would
decrease,causing the On time of the pulse on Pin 3 to
increase.This is used to keep the 130 volt supply at the
correct voltage.Variable resistor 3322 is used to adjust the
130 volt supply to the correct level.
The overvoltage protection circuit of the IC will shut the IC
down if the VCC level on Pin 1 exceeds 17 volts.
To troubleshoot this circuit,first check the On/Off line from the
Small Signal Panel to ensure that it is going Low.Then check
for the presence of startup voltage on Pin 1 of the regulator
IC 7302.If the IC is working correctly,this voltage will be
changing from 9.4 to 14.5 volts.If the startup voltage is not
present,check the startup resistor 3300 and the bridge
rectifier.If the voltage on Pin 1 is changing,check the drive
signal on Pin3.Then check for signal on the gate and drain of
7301.An excessive load on the secondary,a short on the 130
volt line for example,would cause the supply to pulse with
little or no voltage on the secondary.
Sound Problems
No sound or sound too loud (after channel change / switching
on)
– Enter the Customer Service Mode. If the volume is OK,
increase / decrease the volume level.
5.7.2Picture Problems
Picture Too Dark or Too Bright
– Press “Smart Picture” button on the remote control. If this
improves the picture, increase / decrease the brightness
value or increase / decrease the contrast value.
– Enter the Customer Service Mode. If this improves the
picture, exit Customer Service Mode, then Increase /
decrease the brightness value or increase / decrease the
contrast value.
White Line Around Picture Elements and Text
– Press “Smart Picture” button on the remote control. If this
improves the picture, decrease the sharpness value.
– Enter the Customer Service Mode. If this improves the
picture. Decrease the sharpness value.
Snowy Picture
– Snow is an antenna or antenna connector problem.
Check tuner and AGC.
Black and White Picture
– Press the “Smart Picture” button on the remote control. If
this improves the picture, increase the color value.
– Enter the Customer Service Mode. If this improves the
picture. Increase the color value.
Menu Text Not Sharp Enough
– Press the “Smart Picture” button on the remote control. If
this improves the picture, decrease the contrast value.
– Enter the Customer Service Mode. If this improves the
picture. Decrease the contrast value.
Page 13
8.Alignments
Alignments
GB 79A10PTV2.0 NTSC8.
General: The Service Default Mode (SDM) and Service
Alignment Mode (SAM) are described in Chapter 5.
8.1Alignment Conditions
All electrical adjustments should be performed under the
following conditions:
•Supply voltage : 120V +/- ( 10%)
•Warm-up time: 10 minutes
•The voltages and oscilloscope waveforms are measured
in relation to the tuner ground.
•Test probe: Ri > 10Meg Ohm; Ci < 2.5 pF.
8.2Software Alignments (Service Alignment
Mode)
With the software alignments of the Service Alignment Mode,
the geometry, white tone and tuner (IF) can be aligned.
CL 16532052_003.eps
Figure 8-1
8.2.1 Tuner Options - AFC Window and IF PLL Offset
AFC Window
Enter SAM (see Chapter 5 (Service Alignment Mode)). Press
Cursor Down button to highlight the TUNER menu item.
Press Cursor Right button to enter the TUNER submenu.
Press Cursor Down button to highlight the AFC submenu
item. Use the Cursor Left/Right buttons to toggle the value of
AFC between 100kHz (NORMAL) and 250kHz (ENLARGE).
090501
3. Connect an Oscilloscope to the Collector of each output
transistor on the Green CRT board. Set the probe to
times 10.
4. Adjust the Green G2 control until the Black Level is at
200V.
5. Repeat steps 3 and 4 for the Red and Blue CRTs.
Alternate Method
1. Connect a Black Level signal to the set.
2. Preset all G2 controls on the Focus/G2 Combo Block to
minimum (fully CCW).
3. Turn each G2 control clockwise until each CRT is barely
illuminated.
8.3.2Gray Scale Setup
1. Connect a Gray Scale pattern to the set.
2. Preset the registers as shown below.
NORMAL RED26
NORMAL GREEN56
NORMAL BLUE59
NORMAL BLACK LEVEL RED10
NORMAL BLACK LEVEL GREEN13
DELTA COOL RED-6
DELTA COOL GREEN-7
DELTA COOL BLUE4
DELTA COOL BLACK LEVEL RED2
DELTA COOL BLACK LEVEL GREEN1
DELTA WARM RED6
DELTA WARM GREEN0
DELTA WARM BLUE-8
DELTA WARM BLACK LEVEL RED-2
DELTA WARM BLACK LEVEL GREEN-1
CATHODE DR12
1. Set Brightness, Color, and Sharpness controls to 40 and
Picture control to maximum.
2. Adjust the NORMAL BLACK LEVEL controls to set the
correct gray scale in the dark areas of the picture.
3. Adjust the NORMAL RED AND BLUE controls to set the
correct gray scale in the light areas of the picture.
4. Use the Menu button on the Remote to back out to the
main service menu.
5. Turn the set Off using the Power Button on the Remote
or the front of the set.
8.4Convergence Procedures
IF PLL Offset
NO ADJUSTMENT IS NECESSARY FOR THIS MENU
ITEM
The default value for these options is:
•IFPLLOFFSET:32
8.3Gray Scale Alignment
Gray Scale alignment will be necessary after changing the
SSB (Small Signal Board) or the CRTs.
Enter the Service Alignment Mode by entering 0-6-2-5-9-6(Status or Index).
8.3.1G2 Setup
Preferred Method
1. Connect a Black Level signal to the set.
2. Preset all G2 controls on the Focus/G2 Combo Block to
minimum (fully CCW)
The set should be warmed up for at least 20 minutes prior to
making any Geometry or Convergence adjustments.
A signal must be applied to the set while performing
Convergence or Geometry alignments. This is necessary to
provide the correct horizontal and vertical sync to the
Convergence panel. Failure to do so will result in an out of
convergence picture when signal is applied to the set.
The Serviced Technician should sit at least 5 to 10 feet from
the front of the screen while doing Convergence. Ensure
that you are eye level with the area of the screen you are
adjusting.
When performing Digital Convergence, the adjustments are
interactive. A change in one quadrant will affect adjacent
areas of the screen. Several passes through the
Convergence sequence may be necessary. When doing
Convergence, it is advised to follow the sequence pattern
when going fromon adjustment location to another. Pressing
the Right Cursor key will sequence the Icon through a
preloaded sequence.
Page 14
GB 80A10PTV2.0 NTSC8.
When the Convergence error is small, a touch up
Convergence will be all that is necessary. Do not adjust
Green Geometry while in this mode. A compete in-depth
Convergence is required when the Small Signal Module
(SSM) or the Convergence Memory IC, has been replaced.
If the SSB (Small Signal Board) or the Large Signal Board
(LSB) has been replaced, a complete in-depth Geometry
should be completed before Convergence is adjusted. The
Geometry alignment should not be necessary if the SSB or
LSB have not been changed.
8.4.1Screen Templates
When performing a complete in-depth Convergence
alignment, a Screen Template is necessary to obtain the
correct Geometry. The correct Templates are listed below:
2. Enter the Convergence mode by entering 0-6-2-5-9-7(Status or Index). Select an active channel or input. If
the Customer settings need to be adjusted, pressing the
Menu button will access the Customer menu.
3. Place a Template over the screen.
4. Select GREEN in the SELECTION menu.
5. Place a jumper across connector 1005 on the SSM to
defeat convergence drive.
6. Using the centering rings on the Green CRT, center the
convergence pattern onto the center point of the
Convergence Template.
7. Press the Menu button on the Remote to return to the
SELECTION menu.
8. Select RED TO GREEN in the menu.
9. Center the Red pattern onto the Green pattern.
10. Select BLUE TO GREEN in the SELECTION menu.
11. Center the Blue pattern onto the Green pattern.
12. Remove the Jumper on connector 1005.
8.4.2Touch-up Convergence Adjustments
Enter the Digital Convergence Mode (DCM) by entering 0-62-5-9-7-(Status or Index) on the Remote control. The
following menu will appear:
Select an active channel or Aux Input. A signal must be
applied to the set when performing convergence. If any
Customer Adjustments need to be made, the Menu button
can be used to toggle between the Customer Menu and
DCM. The MPOSD ADJUST is used to center the Customer
Convergence grid. A highlighted cross will appear along with
the Convergence alignment grid. The highlighted cross
should be centered onto the center of the Convergence grid.
To perform a Touch Up Convergence, highlight SELECTION
and press the right cursor button on the remote. The
following menu will appear:
Selections STORE, RESTORE FACTORY, and RESTORE
DEFAULT are not shown after selecting SELECTION. Press
the cursor down button on the Remote for these selections to
appear. RESTORE FACTORY loads Convergence defaults
from the Factory Loaded section of the Convergence
Memory IC. RESTORE DEFAULT loads Convergence
defaults from the sets software.
To perform a Touch-up Convergence:
1. Enter the Convergence Mode and select RED TO
GREEN or BLUE TO GREEN. Do not select GREEN
(Green Geometry) without placing a Template over the
screen. To perform Green Geometry, refer to the
Complete in-depth Convergence.
2. Use the Cursor buttons on the Remote to Navigate from
one adjustment point to another. Press the Status or
Index button on the Remote to select ADJUST. Use the
cursor buttons on the Remote to adjust the Red to Green
or Blue to Green. Press the Status or Index button again
to navigate to the next adjustment location.
3. After Convergence alignments are complete, press the
Menu button on the Remote to return to the SELECTION
menu.
4. Highlight the STORE selection and press the right cursor
key on the Remote to save changes.
5. Use the GREEN TO RED or GREEN TO BLUE
selections to perform convergence when the Green CRT
has been replaced.
Note: If a CRT has been replaced, it is only necessary to
perform Screen Centering for the CRT being replaced.
8.4.4Green Geometry
1. Make sure a signal is applied to the set.
2. Enter the Convergence mode by entering 0-6-2-5-9-7(Status or Index). Use the Menu button to toggle
between DCM and Customer Mode. Select an active
channel or input while in the Customer Mode.
3. Place a Template over the Screen.
4. Select GREEN in the SELECTION menu.
5. The Icon will appear in the center of the screen. Press
theRightCursorkeyontheremotetomovetheIconto
the next adjustment location. At each location press the
Status orIndex button to enter the ADJUST mode. Using
the Cursor keys, adjust the Icon onto the adjustment
point on the template. It is recommended that the two
outside vertical lines not be adjusted in the first two
passes.
6. Continue to follow the pattern and make corrections until
the Convergence Crosshatch pattern matches the
Template.
7. Press the Menu button to return to the SELECTION
menu.
8. Use the Cursor down key to highlight the STORE
selection.
9. Press the Right cursor key to save the alignments.
10. Remove the Template.
8.4.5Red Convergence
1. Select RED TO GREEN in the SELECTION menu.
2. Adjust the Red crosshatch pattern onto the green pattern
in the same manner that Green was adjusted to the
Template.
3. Save the alignments.
8.4.6Blue Convergence
1. Select BLUE TO GREEN in the SELECTION menu.
2. Adjust theBlue crosshatch pattern onto the greenpattern
in the same manner that Green was adjusted to the
Template.
3. Save the alignments.
Page 15
Alignments
GB 81A10PTV2.0 NTSC8.
8.5Complete In-Depth Geometry
To activate the Service Alignment Mode, enter 0-6-2-5-9-6(Status or Index) using the Remote Control.
Press Status or Index toggle to the Customer menu. Select
an active channel. Pressing the Status or Index button will
bring up the SAM mode.
Apply a Crosshatch pattern to the set and select that input.
Defeat Convergence by shorting the two pins of connector
1005 on the SSM.
Press the Cursor-down key on the remote and select
Geometry with the Right cursor key.
Adjust the Screen Geometry as necessary.
The following are default values:
VER.AMPL30
VER.SLOPE34
SERV.BLKOFF
HOR.SHIFT32
HOR.BOW20
HOR.PARALLEL 31
EW.WIDTH22
EW.PARA21
EW.TRAP19
EW.UCORN6
EW.LCORN0
H60.WIDTH2
H60.PARA0
H60.SHIFT7
V60.AMPL0
VER.SCOR18
VER.SHIFT35
VER.ZOOM32
VER.SCROLL32
•Adjust Vertical heightVER-ZOOMxx
•Adjust Vertical posistionVER-SCROLLxx
•Adjust Vertical linearityVER-SCORxx
•Not usedH60-SHIFTxx
•Not usedV60-AMPLxx
•Adjust Horizontal widthEW-WIDTHxx
•Adjust ParabolaEW-PARAxx
•Adjust Up cornerEW-UCORNxx
•Adjust low cornerEW-LCORNxx
•Adjust TrapeziumEW-TRAPxx
•Adjust Horizontal parallelogramHOR-PARALLELxx
•Adjust Horizontal bowHOR-BOWxx
To save changes, use the Menu button on the Remote to
back out to the main menu. Then turn the set Off using the
power button on the Remote or the front of the set. This will
save any changes made.
8.6Geometry Adjustment
The geometry alignments menu contains several items for
correct picture geometry alignment. In widescreen models,
the GEOMETRY SW is available for separate alignments of
the superwide (panorama) mode.
8.6.1Initial Set-Up:
Press the PICTURE button on the remote control repeatedly
to change the Smart Picture setting to "NATURAL."
Enter SAM (see Chapter 5 (Service Alignment Mode)).
Press the Menu Down button to select the GEOMETRY
menu item.
Press the Cursor Right button to enter the GEOMETRY
submenu.
Press the Cursor Down button to highlight the VER-SCOR
submenu item.
Use the Cursor Right buttons to adjust VER-SCOR.
VER-SCOR aligns the vertical linearity, so that the vertical
intervals of the grid-patterns are the same over the entire
height of the screen.
Extra Alignment for 4:3 Sets
•Set Service blanking onSERV-BLK ON
•Adjust Vertical slopeVER-SLOPExx
•Set Service blanking OFFSERV-BLKOFF
General Alignment (4:3 set)
•Adjust Vertical amplitudeVER-AMPLxx
•Adjust Vertical shiftVER-SHIFTxx
•Adjust Horizontal shiftHOR-SHIFTxx
Page 16
GB 82A10PTV2.0 NTSC8.
Alignments
8.7Options
Options are used to control the presence / absence of certain
features and hardware. There are two ways to change the
option settings:
1. Changing asingle option: An option may be selected with
the MENU UP/DOWN keys and then changed with the
MENU LEFT/RIGHT keys.
2. Changing multiple options by changing option byte
values: Option bytes make it possible to set all options
quickly. An option byte represents a number of different
options. All options of the A10 PTV are controlled via 8
option bytes. Select the option byte (OB1, OB2, OB3,
OB4, OB5, OB6, OB7 or OB8) and enter the new value
by using the number keys on the remote control.
8.7.1List of Options
The table below gives an overview of possible options. These
option bits can be set ON (1) or OFF (0). If an option is set
ON, it represents a certain value. (see Option bits/bytes).
Adding the value of 8 option bits gives the value of an option
byte (OB).
Option
abbreviation
ABSYAUTO STANDBY AFTER NO INTERAC-
SBNPAUTO STANDBY NO PICTUREON
CVICOMPONENT VIDEO INPUTON
C169COMPRESS 16:9 MODE AVAILABLEOFF
E149EXPAND 14:9 MODE AVAILABLEOFF
HWBMS HARDWARE BLUE MUTE STREAKON
SMCKSMART CLOCKON
AV3SIDEAVSOURCEON
AUSBAUTO STANDBY AUTO ONON
CBFLCOMB FILTERON
IPIXINCREDIBLE PICTUREON
IPMUINCREDIBLE PICTURE VIA MENU ITEM ON
VDBYVIRTUAL DOLBY ENABLEDON
PITNPHILIPS TUNEROFF
PLSTPROGRAM LISTON
SOSDSMART OSDON
BLMUBLUE MUTEOFF
PIPCPIP CONTROLON
PIPSPIP SURFON
PIPTPIP TUNERON
ISURINCREDIBLE SURROUNDON
W4x3DOUBLE WINDOW WITH 4:3 MAIN PIC-
W169DOUBLEWINDOWTWOCOM-
VSLCVERTICAL SLICINGON
SURFSURF FEATURE AVAILABLEON
CCAPCLOSED CAPTIONON
DNRMDNR FUNCTION AVAILABLEON
VMUTVIDEO BLANKING DURING CHANNELCHON
3AP1 & 3AP2 CODE DESCRIPTIONSD
TION
TURE AVAILABLE
PRESSED 16:9 AVAILABLE
OFF
ON
OFF
Option
abbreviation
NVMNVM CORRUPTIONON
HWBMS HARDWARE BLUE MUTE STREAKOFF
OB1CAN BE USED TO ADJUST OPTION
OB2246
OB3251
OB4253
OB5112
OB6OB8
8.7.2Option Bits / Bytes
An option byte value is calculated in the following way:
value “option bit 1” x1=
value “option bit 2” x2=
value “option bit 3” x4=
value “option bit 4” x8=
value “option bit 5” x16=
value “option bit 6” x32=
value “option bit 7” x64=
value “option bit 8” x 128 =
Total is value is “option byte” =
3AP1 & 3AP2 CODE DESCRIPTIONSD
BYTES AT ONCE
99
0
TIMETIMER FEATURE AVAILABLEON
AAVLAVL AVAILABLEON
CHLKCHILD LOCK FEATURE AVAILABLEON
ROTIROTATION/TILTOFF
SNICSOUND BOARD PRESENTON
TMWINTIMEOUT FOR DIGIT ENTRY ON=5SEC
OFF=2SEC
INCFINTERNAL COMB FILTER PRESENTON
OFF
Page 17
9.Circuit Description
Circuit Description
GB 83A10PTV2.0 NTSC9.
The A10 PTV chassis is designed for release in the 20002001 model year. This product is scheduled for release in the
NAFTA and Asia Pacific regions. The set is built in three
screen sizes, 43 inch (109 cm), 50 inch (127 cm), and 55 inch
(140 cm). These sets are capable of receiving signals in the
PAL/D, PAL/I, PAL/BG, NTSC, or NTSC/M formats
depending on the package for a particular country. The set
is equipped with a two tuner PIP. The set has three
composite Video inputs, two on the Rear Jack Panel and one
on the Side Jack Panel. The set also has two SVHS inputs,
and one component input. A Center Channel Input on the set
allows the speakers in the set to be used as a centerchannel.
The MG99 Projection TV uses three single color tubes, Red,
Green, and Blue. The output of each tube is projected onto a
mirror where it is then reflected onto a viewing screen. The
Tubes are converged so the light from each tube strikes the
same spot on the Fresnel Lens. The Fresnel Lens equalizes
and Concentrates the light to provide equal light uniformity
across the screen. The Mirror is a first surface mirror type,
which has the reflective coating on the outside of the mirror.
To prevent scratching of this surface, always use a soft
cotton cloth to clean it.
The Lenticular Lens Screen calumniates the light from the
Fresnel Lens. The Lenticular Lens increases contrast by
reducing the ambient light by the use of Black Striping. The
Prismatic formation of the screen allows for nearly 3X light
output as compared to a flat screen. Caution should be used
when working with the screen. Damage can easily occur in
the form of scratching, or by using certain chemical screen
cleaners which can strip the black striping from the screen.
The clean the screen, use one drop of dish washing
detergent in a small bowl of water. (Approximately 2 liters)
Wipe the screen with a soft cotton cloth in the direction of the
stripes.
on if one is present. This circuit produces a +5 volt and a
+3.3 volt standby voltage. The +5 volt standby voltage
supplies power to the Full Power Supply Relay while the +3.3
volt standby voltage is applied to the Microprocessor
(Painter) located on the Small Signal Board.
When the Microprocessor pulls the Standby line Low, the
Startup Run Switch is turned On, switching the Neutral side
of the AC Mains to the Full Power Supply. This provides the
Startup voltage for the Full Power Supply. Once the Full
Power Supply is operating, a 14 volt supply is generated to
provide operating voltage. The Full Power Supply provides
a 130 volt supply for the Scan circuits, a plus and minus 32
volt supplies for the Convergence circuits, a +15 volt supply
for the Scan supply, a +15VSSB supply for the Signal
circuits, and a AMP_VCC supply for the Audio Amplifier
circuits.
9.1.2AC Input circuit with Power Factor Correction.
The AC Mains are connected to 1108, pins 1 and 4. The ac
is fused by 1000 and then fed to two line chokes, 5000 and
5001. Spark gaps 1003, 1002, 1001, 1005, and 2004provide
lighting protection. AC is then routed through the AC Mains
Switch before being applied to the Power Factor Correction
circuit.
The Three CRT’s are driven by 30KV of high voltage and
15KV of focus voltage. The Tube produces a highly
concentrated light output of color. A liquid coolant of Glycol
is used to transfer heat from the face of the tube to the
surrounding mechanical assembly. The C-element lens
seals the Coupling fluid within the coupler. The C-element
lens and Coupling fluid are part of the light path and
contribute to the properties of the optical system.
9.1Power Supply
9.1.1Power Supply Block
AC Mains are fed to the PFC (Power Factor Correction) or
Line Conditioner. The output of this panel is fed to the
Standby and Full Power sections, which are located on the
Large Signal panel. The AC mains voltage is 230 volts for
sets with the Power Factor Correction circuit. The ac Mains
voltage can be either 115 or 230 volts for the multi-voltage
sets. There are two dc output voltages from this panel, which
are 160 to 325 volts dc to the Standby Power section on the
Large Signal panel and 160 to 380 volts dc to the Full Power
Section. The 160 volts dc is present is the AC Mains are 115
volts. The 325 volts dc is present if the AC Mains are 230
volts. If the Power Factor Correction circuit is present, 380
volts dc is present. If the Power Factor Corrections circuit is
present, the circuit is switched off when the set is in the
Standby mode. The Standby Line is switched low when the
set is turned on, switching the operating voltage from the
Standby Power Section to the Power Factor Correction
circuit.
CL 06532143_008.eps
Figure 9-1
9.1.3AC Input circuit without Power Factor Correction.
The AC Mains are connected to 1108, Pins 1 and 4. The ac
is fused by 1000 and then fed to three line chokes, 5000,
5001, and 5005. The AC Mains voltage is applied to bridge
6000 and filtered by 2110 to produce the Main B+ voltage.
The AC Mains are also connected to bridge 6001 to produce
RAWSTBY voltage for the Standby Section of the power
supply. This circuit is fused by 1004. Startup voltage for the
Full Power Section is taken from the Neutral side of the AC
Mains and fed to the Full Power Section on the Large Signal
Panel through resistor 3300.
081100
The Standby Power Section begins operating as soon as
power is applied to the set and the AC Mains Switch is turned
Page 18
GB 84A10PTV2.0 NTSC9.
Circuit Description
Figure 9-2
Figure 9-3
CL 06532143_009.eps
081100
CL 06532143_010.eps
081100
9.2Power Factor Correction Circuit
The input to most switching power supplies consists of a
bridge rectifier and a large electrolytic capacitor when AC
power is applied, the Capacitor will charge to approximately
1.4 times the RMS value of the applied AC voltage. This type
of supply does not draw current from the AC power source
through out the entire AC cycle. When the capacitor charge
falls to point “A”, the instantaneous value of the AC voltage
exceeds the charge of the capacitor. The bridge diodes are
then forward biased, causing current to flow from the AC
source. Current will continue to flow from the AC line until the
AC sinusoidal voltage reaches its peak at Point “B”.Atthis
point, the charge on the capacitor will exceed the AC line
voltage reversing the bridge diodes. This results in an AC
current waveform that is narrow and distorted compared to
the AC voltage waveform. Non sinusoidal waveforms have a
high harmonic content, with excessive peaks, which results
in a low power factor of 0.5 to 0.6. Power Factor is a ratio of
real power divided by apparent power. Excessive harmonics
and peak currents reduce the efficiency of the power
distribution system. The A10 Projection TV without Power
Factor correction has a high harmonic content of 85 percent,
creating a Power Factor of 0.5. High current spikes will also
be created in the AC supply. With the Power Factor
correction circuit, the peak current is limited, with the
harmonic content being reduced. The Power Factor is
increased to 0.99. The ideal Power Factor is one, which
occurs when the current is sinusoidal and in phase with the
voltage. Many countries limit the current harmonic content
of equipment supplied by the AC Mains. The A10 Power
Factor correction circuit uses a Boost regulator to smooth out
the current draw from the ac line improving the Power Factor
to 0.99, which is accomplished by drawing current from the
AC source throughout the entire ac cycle making the current
waveform sinusoidal. Input to the module is connected to the
ac Mains. The output supplies are approximately 376 volts
dc to the Main and Standby Switched mode Power Supply
circuit. The Boost Regulator circuit produces a higher output
voltage than the input voltage. The regulator drive circuit
compares 6103’s output voltage, the input voltage from the
bridge, and the voltage across the current sensing resistors
to control the On time of 7104. This will maintain the output
voltage at 376 volts DC and limit the input current to
Page 19
Circuit Description
GB 85A10PTV2.0 NTSC9.
acceptable levels. When 7104 is on, current flow through
5109 stores energy in the choke. When 7104 turns off, 5109
reverses polarity and charges 2109. Using this type of
regulation, current is drawn from the AC source throughout
the entire cycle, keeping the current waveform sinusoidal.
When the AC cycle is at its low point, 7104 is on for a longer
period of time. When the AC voltage is at its peak, 7104 is
on for a shorter time to store the same amount of energy in
5109 to maintain the output voltage at 376 volts dc. If the
Boost regulator circuit should become inoperative, due to a
loss of regulator drive, operating voltage is still applied to the
set. The supply voltage to the switching supplies will drop
from 350 volt to approximately 329 volts depending on the
Mains voltage. Since the customer would not detect a failure,
the operation of this circuit should be checked after any
repair of the set.
3131, 3132, and 3133. This sample is added to the error
signal from the Multiplier going into Pin 8. The error signal is
amplified and then compared to the oscillator ramp to
determine the reset point for the latch. When the oscillator
goes low, the latch is set making output “Q” High. With the
other inputs to the AND gate High, Pin 20 then goes High,
turning 7104 On. By comparing the input and output voltage,
the on time of 7104 is increased when the ac voltage is at its
low point to maintain the 376 volt dc output. When the acinput voltage is at its peak, 7104 is on for a shorter period.
The IPK circuit connected to Pin 2 is an overcurrent
protection circuit, which resets the latch if there is excessive
current through the return resistors. This will reduce the on
time of 7104. In a like manner, the OVP, Over Voltage
Protection, circuit will reset the latch removing drive to Pin 20
is the output voltage exceeds 392 volts.
To check the operation of this circuit when the set is
operating correctly, check the PFCOUT voltage. This
voltage should be approximately 376 volts. If the output
voltage is approximately 300 to 329 volts, this circuit is not
working. Check the operating voltage on Pin 19 of 7102.
Then check the output drive on Pin 20 and at the gate of
7104. There are three grounds on the hot side of the supply.
Ground HA is connected directly to the bridge 6000. Ground
“B” is the ground for the Power Factor Correction circuit. If
the current sensing resistors 3130 through 3133 should
open, this would remove the ground for all the switching
supplies and make the set inoperative. Ground “C” is the
ground for the switching supplies. When ground “B” passes
through the choke 5106, it becomes ground “C”.
Figure 9-4
Figure 9-5
9.3Full Power Factor Correction Circuit
The Power Factor Correction circuit is a fixed-frequency
Pulse-Width modulated boost regulator power supply.
Operating frequency is approximately 60 kilohertz. Due to
the low power consumption of the set during the standby
mode, the Power Factor Correction circuit is turned off. The
operating voltage, PFC, on Pin 19 of 7102 is turned off.
When the set is turned on, the operating voltage is switched
to Pin 19 of 7102. Once the circuit is in operation, a 5.11-volt
internal reference voltage on Pin 11 is applied to Pin 6 of the
IC. Output of the bridge rectifier is fed to the IC on Pins 4 and
7. Feedback from the output circuit is fed to Pin 14 where it
is multiplied with the Bridge output. Inputs to the Gilberts
Multiplier produce an error signal that is fed to the current
amplifier. The Gilberts Multiplier multiplies the bridge output
voltage with the output voltage on D438. The 5.11-volt
reference is used to provide a clamping reference for the
other inputs. Input current is sampled by resistors 3130,
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081100
Startup up voltage for the Full Power supply is taken from the
neutral side of the AC mains via resistor 3300 and connector
1100 pin 1.
The AC Mains is also rectified by bridge 6001 to produce
RAWSTBY for the Standby Supply.
Page 20
GB 86A10PTV2.0 NTSC9.
Circuit Description
9.4Standby Power Supply
The Standby Power Supply provides 3.3 and 5-volt standby
voltages and operating voltage for the Power Factor
Correction circuit. When ac voltage is applied to the set and
the AC Mains Switch is turned On, RAWSTBY is developed
and applied to the Standby regulator 7211 through Pins 2
and 4 of the Standby transformer 5202 to Pin 5. The Startup
voltage is developed by charging capacitor 2283 through the
internal startup resistor Rs. When 2283 is charged to 5.7
volts, the IC switches to the internal supply. Power is now
supplied by the charge on 2283. The Pulse Width Modulator
will drive the internal switch to drive the Standby transformer
5202. The IC will continue to switch the transformer until the
charge on 2283 falls below 4.7 volts. Capacitor 2283 will
again be charged by the internal resistor and process will
repeat itself. Voltage is developed from the HOT secondary
winding on Pin 5. This voltage is rectified by 6207 to produce
operating voltage for the HOT secondary. Voltage from Pin
9 is rectified by 6231to produce the 3.3-volt Standby voltage.
When the 3.3-volt Standby voltage has reached the correct
level, it will turn the Shunt Regulator 6205 on. This drives the
Opto-isolator 7213, which switches the HOT secondary
operating voltage to Pin 4 of 7211 through resistor 3287. Pin
4 of 7211 will not stay at a constant 5.7 volts to provide the
operating voltage for the IC. Regulation is accomplished by
the Shunt Regulator 6025, Opto-isolator 7213, and the
internal current sensing resistor of 7211. This circuit also
produces a 5-volt standby voltage and Reset via 7209 and
7208.
Figure 9-6
CL 06532143_013.eps
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When the Set is turned on, the Standby line is switched low
by the Microprocessor on the SSB. Transistor 7214 is turned
off, which turns 7205 on, turning 7206 on. This turns
transistor 7204 on, switching operating voltage to the Power
Factor Correction panel via connector 1502, Pin 1.
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Circuit Description
GB 87A10PTV2.0 NTSC9.
9.5Full Power Supply
When the set is turned on, the Main Switch Mode power
supply is turned On This supply produces the +130 volt, +32
volt, -32 volt, two +15 volt, and Audio supplies. When the On/
Off line goes low, transistor 7309 is turned off, turning
transistor 7300 on. This switches relay 1305 on. Startup
voltage from the neutral side of the AC mains will charge
capacitor 2303 to 14.5 volts, which will overcome the
undervoltage lockout of IC 7302. After the Soft start
capacitor 2443 charges; the oscillator inside the IC will turn
on. Each cycle of the oscillator will set the flip-flop, which will
cause Pin 3to gohigh. This willturn the FET switch7301 on.
Voltage is applied to the Drain of 7301 through Pins 4 and 8
of 5300 from the Power Factor Correction circuit. Current
through sensing resistors 3308 and 3309 will develop a
voltage, which is applied to comparator “B” connected to Pin
7. When the voltage on Pin 7 reaches the reference voltage
on the inverting input, the flip-flop will be reset. The voltage
on the inverting side of comparator “B” is limited to 1 volt.
Therefore, the ramp voltage on Pin 7 will not exceed 1 volt.
The circuit will continue to operate until the charge on
capacitor 2303 falls below 9.4 volts shutting the IC Off. Each
time 7301 is turned on; energy is stored in transformer 5300.
Voltage from the hotsecondary onPin 10is rectifiedby 6301.
When the output of this circuit has sufficient energy to
maintain 2303 above 9.4 volts, the IC then operates in steady
state.
Figure 9-7
CL 06532143_014.eps
When IC 7302 develops a normal steady state operation, the
130-volt supply is sampled by resistors 3324, 3323, and
3322. This sample voltage is then sent to Shunt regulator
7303, which drives the feedback optoisolator 7303. The
feedback voltage on Pin 14 is then compared with an internal
2.5-volt reference by comparator “C”. Comparator “C” then
sets the reference voltage on the inverting side of comparator
“B” to control the On time of the drive at Pin 3. If the voltage
on Pin 14 increases due to the 130-volt supply increasing,
the On time of the pulse on Pin 3 will be reduced. If the 130volt supplydecreases, the voltage on Pin 14 would decrease,
causing the On time of the pulse on Pin 3 to increase. This
is used to keep the 130-volt supply at the correct voltage.
Variable resistor 3322 is used to adjust the 130-volt supply to
the correct level.
The overvoltage protection circuit of the IC will shut the IC
down if the VCC level on Pin 1 exceeds 17 volts.
To troubleshoot this circuit, first check the On/Off line from
the Small Signal Panel to ensure that it is going low. Then
check for the presence of startup voltage on Pin 1 of the
regulator IC 7302. If the IC is working correctly, this voltage
will be changing from 9.4 to 14.5 volts. If the startup voltage
is not present, check the startup resistor 3300 and the bridge
rectifier. If the voltage on Pin 1 is changing, check the drive
signal on Pin3. Then check for signal on the gate and drain
of 7301. An excessive load on the secondary, a short on the
130-volt line for example, would cause the supply to pulse
with little or no voltage on the secondary.
081100
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GB 88A10PTV2.0 NTSC9.
Circuit Description
Voltage regulator 7611 produces an 8-volt supply for the
Audio Processor located on the SSB panel. Regulator 7612
produces a 12-volt source for the Video Output circuits
located on the SSM panel. Both of these regulators are
powered by the +15SSB source from the Full Power Section.
Figure 9-8
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Figure 9-9
9.65.2 Volt Regulator
A 5.2-volt source is developed by 7308 and 7307. The Pulse
Width modulator in 7307 drives transistor 7308 to produce
the source. Feedback for regulator is sampled by resistors
3339, 3340, and 3334 where it is fed to Pin 5 of 7307. This
circuit is powered by the 15 volt supply from the Full Power
Section. This source is fed to the SSB panel.
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Page 23
Circuit Description
GB 89A10PTV2.0 NTSC9.
9.7Video Signal Flow
Video input for the A10 PTV can be from either of two tuners,
three composite inputs, two SVHS inputs, or from a
component input. The Main Tuner is located on the SSM
panel and is controlled by a data line from the
Microprocessor located on the SSB Panel. IF from the Tuner
is fed to a switched Saw Filter circuit.
The Saw Filter circuit is made up of a PAL/SECAM Saw
Filter, 1455, and an NTSC Saw Filter, 1451.When the SELIF-LL line is Low, transistor 7413 is turned Off, switching
1451 On, turning transistor 7414 On which turns the PAL/
SECAM Saw Filter 1454 Off. When the SEL-IF-LL line is
High, 7413 is turned on, turning 7414 and the NTSC Saw
Filter 1451 off. A positive voltage will be applied to 1454, the
PAL/SECAM Saw Filter, turning it On. VSIF1 and VSIF2 is
output to the Audio processor from the Audio Saw Filter,
1455.
Video IF is fed to Pins 1 and 2 of 7301, which outputs
composite video on Pin 16. The composite video is buffered
by 7305, filtered by 1333, buffered by 7331, and fed to Pin 24
of 7301. This section of the Signal Processor selects
between composite video from the Main Tuner and External
Video or Luminance from7401. The selected Video or
Luminance is buffered by 7421 and fed to the Comb Filter
7405. If the input on Pin 12 is Composite Video, the Comb
Filter is switched on. If the input on Pin 12 is Y (Luminance)
and the input on Pin 1 is Chroma, the Comb Filter is switched
off. Luminance and Chroma is then fed to the Signal
Processor on Pins 20 and 21. YUV is then output on Pin 40,
45, and 46 to 7403, Video Enhancement circuit. IC 7403
provides Luminance processing, Colour vectors processing
and spectral processing. In the Luminance processor, the
luminance is processed in 5 discrete histogram sections. As
a result, the contrast ratio of the most important parts of the
scene will be improved. In the Colour Vector Processor, the
dynamic skin tone correction locally changes the hue of
colours that match skin tones to the correct hue. The Green
Enhancement circuit activates medium saturated green
towards to a more saturated green. The Blue Stretch circuit
can be activated which shifts colours near white towards
blue. The Spectral Processor provides luminance transient
improvement. YUV from 7403 is fed to the PIP/DW (Picture
in Picture/Double Window) panel.
Figure 9-10
CL 06532143_017.eps
YUV is fed to 7801, PIP/DW IC, and 7803, Switch IC, on the
PIP/DW panel. If the PIP/DW function has not been
selected, 7803 switches the YUV signal back to 7301 on the
SSB panel. Video for the PIP or Double Window is selected
by the user from the second tuner located on the PIP/DW
panel or from composite video from the SSM. IF from the
PIP/DW tuner is fed to a switchable Saw Filter 1352. The
Reset line switches the filter between NTSC and PAL/
SECAM. The output of the Saw filter is fed to the Signal
Processor 7301. This Saw Filter is located on the PIP/DW
panel. Composite video is then fed to Pin 24 of 7301, which
selects between the second tuner or selected Composite or
SVHS on Pins 29 and 20. YUV, labeled SY, SU, and SV is
then fed to the PIP/DW IC 7801. YUV from 7801 is fed to the
switch IC 7803.
On the Rear Jack panel, there are two Composite Video
inputs, one SVHS input, and one Component input. The Y or
Luminance signal from the Component input is fed to a YSharpness circuit and then fed to switching IC 7711 along
with the PB and PR signals. The YUV signal is then fed to
7301, Signal Processor located on the SSB panel. The Y
signal is also fed to 7712 where it is fed to 7401 and then to
7301. Since the Sync is on the Y signal in a Component
signal, the Y signal must be switched on this path for Sync
separation. If the set is in the Convergence adjustment
mode, 7711 selects Red, Green, and Blue drive from the
Convergence Circuit. Therefore, the inputs on Pins 41, 42,
and 43 of 7301 can be either YUV or RGB depending on the
selection made inside the IC. RGB and Fast Blanking for the
On Screen Display from the Microprocessor (Painter) is fed
to 7301 on Pins 35, 36, 37, and 38.
Brightness, Contrast, Colour, Colour Temperature, RGB
cutoffs and drives, and Tint (NTSC) are all controlled inside
7301. RGB is then output on Pins 33, 32, and 31 to the RGB
amplifiers, located on the SSM Panel.
081100
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GB 90A10PTV2.0 NTSC9.
Circuit Description
Figure 9-11
Figure 9-12
CL 06532143_018.eps
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Page 25
Circuit Description
GB 91A10PTV2.0 NTSC9.
9.7.1CRT Drive Circuit
Red, Green, and Blue drive from the SSB panel is fed to the
CRT drive circuit on the SSM PANEL. Red drive is fed to
transistors 7600 and 7602. Green drive is amplified by 7603
and 7605. An additional amplification circuit is added to the
Blue circuit to provide added gain. This is called the Blue
Stretch circuit. This circuit consists of transistors 7606, 7607,
and 7613.
Transistors 7601, 7604, 7609 provides CRT blanking. In the
event of a Sweep failure, the High on the CRT protection line
from the High Voltage Scan circuit will go low. Diodes 6602,
6605, and 6610 will turn the blanking transistors on.
When the G2SETUP line goes low, diodes 6606, 6600, and
6603 are forward biased, blanking drive to the CRT's.
The Red, Green and Blue Drive is fed to the Green CRT
panel along with a 12 volt bias. Red and Blue drive from the
Green CRT panel is routed to their respective CRTs.
Filament voltage and the 240 volt CRT drive voltage from the
Scan High Voltage panel is fed to the Green CRT panel.
Figure 9-13
CL 06532143_020.eps
voltage, which is fed to the SSB panel. The Cutoff voltage is
fed to Pin 34 of 7301 to set drive levels for the RGB out. The
Black Current stabilization system checks the output level of
3 channels and indicates whether the black level of the
highest output is in a certain window.
081100
Beam Current information IKR, IKG, and IKB are fed to the
SSM panel where they are combined to provide a Cutoff
Page 26
GB 92A10PTV2.0 NTSC9.
Circuit Description
Figure 9-14
Figure 9-15
CL 06532143_021.eps
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9.7.2SVM Circuit
Luminance drive from the SSB panel is fed to the SVM panel
via connector via 1804, Pin 3. The signal is amplified by
Q751 and Q753. The coil L752 and Capacitor C755 makes
up a differentiation circuit to detect light to dark and dark to
light transitions. The detected signal is fed to a Power
Amplifier, which drives SVM Yokes on each of the CRT’s.
This drive speeds up the pulse during luminance transitions
to sharpen the edges, increasing picture sharpness. Fast
Blanking is fed to transistor Q755 to blank drive to the SVM
amplifier for areas of the screen where On Screen Display is
present. This panel is powered by the 15 and 130-volt
sources.
Page 27
Figure 9-16
9.7.3Line Drive
Line Drive from the SSB Panel is fed tobuffer transistor 7803.
(Figure 13) Transistor 7803 then drives the Line driver
transistor 7801. Line drive is then fed to the Line output
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Circuit Description
transistor 7802. Transistor 7802 drives the three Line Yokes
and the Scan transformer 5801. The Scan transformer
produces a 240 volt supply for the CRT drive circuits, a
Filament drive for the CRT’s, a plus and minus 13 volt supply
for the Frame drive circuit. It also produces a 32-volt supply
for the beam limiter circuit in the High Voltage circuit. The
output of the Line Output transistor 7802 is also fed to buffer
transistors 7800 to produce a Line feedback pulses to the
SSB Panel (HFB).
Drive for geometry correction from the Small Signal panel on
the E_W line drives transistors 7553, 7551, and 7552. This
circuit drives the return side of the Line Yokes to provide
Horizontal corrections to the geometry. Geometry correction
drive, E_W, is also fed to transistor 7830 which produces
drive for the Dynamic Focus, LV. The Line component to the
Dynamic Focus is added in transformer 5802.
GB 93A10PTV2.0 NTSC9.
9.7.4Frame Drive Circuit
Frame Drive from the Small Signal panel (FDRVP and
VDRV) is fed to the Frame Output IC 7550. (Figure 14) This
circuit is powered by a +13 volt supplyconnected to Pin 8 and
a -13 volt supply connected to Pin 6 whichare supplied by the
Line Drive circuit. Pin 5 of 7550 provides drive for the three
Frame yokes. Frame drive feedback from the return side of
the yokes is fed back to Pin 2 of 7550. Frame sync (VPUL)
for the Sweep Failure Detection circuit is output on Pin 4 of
the IC. Output from Pin 7 is buffered by transistor 7590 to
produce a Frame Sync pulse (VFB) for the Small Signal
panel.
Figure 9-17
CL 06532143_024.eps
081100
A failure in this circuit would cause the High Voltage to shut
down. A problem in this circuit could be caused by a loss of
drive from the Small Signal panel or a failure in the Line
Sweep circuit. An open Yoke connection would also cause
the Frame drive from the IC to shut down.
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GB 94A10PTV2.0 NTSC9.
Circuit Description
Figure 9-18
CL 06532143_025.eps
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9.7.5High Voltage and Shutdown
The High Voltage circuit in the A10 PTV chassis is contained
in an integrated High Voltage Module. This circuit is powered
by the 130-volt source from the Full Power supply. The Dag
line from the CRT's is connected to 1574 and to Pin 1 of the
High Voltage module. This line along with the current sense
line from Pin 3 is connected to the Beam Limiter transistors
7905 and 7910. This provides feedback to the RGB output
circuit in IC 7301 located on the SSB panel to make minor
changes in brightness and vertical height.
Figure 9-19
CL 06532143_026.eps
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When the set is turned on, the 130 volts is applied to Pin 10
of the High Voltage module. Transistor 7500 acts as an OR
gate to detect the failure of Frame Sweep (VPUL) or Line
Sweep (170V Pulse). When these pulses appear, 7500 is
turned off, allowing 7501 to turn on. This will apply
approximately 7.5 volts dc to Pin 8 of the High Voltage
module, turning it on. The High Voltage module produces 15
kV for the Focus/G2 block and 30 kV for the CRT's. This also
places aHigh on the CRT_PROT line, allowing the CRT drive
circuits to turn on. If Line or Frame drive should fail, CRT
drive and High Voltage will be shut off to protect the CRT's.
A failure is either drive will cause 7500 to turn On, turning
7501 Off, removing the 7.5 volts from Pin 8 of the High
Page 29
Circuit Description
GB 95A10PTV2.0 NTSC9.
Voltage module, shutting it Off. The CRT_PROT line will also
go low, shutting the RGB amplifiers to the CRT panels off.
In the case of Overcurrent, the voltage on Pin 3 of the High
Voltage module will drop, turning transistor 7909 on, turning
7908 on, latching 7907 and 7908. This will remove the 7.5volt turn on voltage at Pin 8 of the High Voltage module,
turning it off. During turn on, transistor 7906 is biased off
while capacitor 2913 charges. This prevents the shutdown
latch from turning on while the High Voltage module is turning
on.
9.8Digital Convergence Circuit
CRT’s and Yokes are not linear devices. (Figure 28)
Therefore, a convergence circuit is necessary to align the
beams of all three tubes over the entire screen. The
Convergence panel is powered by a +32volt, a -32 and a +15
volt supply from the Power Supply panel. A Line Sync (H
PUL) and a Frame Sync (V PUL) from the Scan High Voltage
panel keeps the Convergence Correction waveforms
synchronized to the deflection system. The SDA and SCL
lines on Pins 32 and 34 allow the microprocessor on the SSM
Panel to communicate with the microprocessor on the SSB
Panel. During the Convergence alignment mode, the
crosshatch pattern is generated in the Convergence circuit.
Red, Blue, Green, and Fast Blanking are fed to the Interface
panel and then to the Small Signal panel to be inserted into
the video drive.
The Convergence correction waveforms may be disabled for
set up procedures by shorting connector 1005.
The output of the dac’s are amplified and filtered by IC200,
IC201, and IC202 before being fed to the Yoke drive
amplifiers.
If for some reason the set needs to be converged in the field,
the csp generates a cross hatch pattern with an intensified
cross. Control for 7003 csp is done by the microprocessor on
the SSB Panel. The R, G, G, Fast Blanking, and Intensity
signals used to display the pattern are output on Pins 29, 30,
31, 25, and 26 on 7003.
There are two plus 5-volt regulators, and a -5 volt regulator in
the convergence circuit. (Figure 29) These are fed by the
plus 15 volt SSB, and the -32 volt supplies from the Large
Signal Panel. The 5-volt supply feeds the microprocessor
while the 5VA supply feeds the Digital to Analog converter
IC’s. The Plus and minus 32 volt supplies provide power to
the output IC's 7012 and 7014.
The Convergence panel has a phase-locked loop oscillator,
which produces a 13.59 MHz signal. (Figure 30) This signal
is phase locked to the 15650 Hz PAL or the 15734 Hz NTSC
Line Blanking pulse (HPUL). This signal is used as the
system clock, which is used by the convergence spline
processor (CSP), and the three digital to analog converters
(DACS). Therefore, the convergence correction waveforms
are synchronized to the deflection system of the television
set. Operational amplifier 7001 is used as an inverting two
pole Sallen_Key filter, which acts as the loop filter. Transistor
7000 and 7001 make up the oscillator.
When the set is turned on, the microprocessor on the Small
Signal panel reads the data stored in 7007 on the
Convergence panel via the I2C bus. This information
contains the x-y coordinates for the 35 alignment points of
each color visible on the screen during convergence set up
along with other register settings used by the csp.
The csp uses fourth order polynomial equations called
quadric splines in the algorithm to convert the data of the 35
(7 horizontal by 5 vertical) alignment points into 24 points per
horizontal 486 vertical lines for NTSC. When using PAL or
SECAM, the algorithm converts the data of the 35 (7
horizontal by 5 vertical) alignment points into 24 points per
horizontal line by 666 vertical lines. The resulting digital data
is supplied to 7009, 7011 and 7010; the three two channel
dacs, which convert the digital data into analog convergence
correction signals for red, green, and blue horizontal and
vertical. The csp outputs are approximately 1 to 2 volts peak
to peak with a 2.5-volt dc offset. The csp also supplies a 375
KHz 5-volt peak to peak ws or word select signal to select the
proper channel on the dac for horizontal (Line) or vertical
(Frame).
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GB 96A10PTV2.0 NTSC9.
Circuit Description
Figure 9-20
CL 06532143_027.eps
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Figure 9-21
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Page 31
Circuit Description
GB 97A10PTV2.0 NTSC9.
9.9Audio Signal Flow
All of the Audio switching is done on the SSB Panel. IF from
the Main Tuner is fed to 1455, Audio Saw Filter and then to
7301 for detection and demodulation. Baseband audio is
buffered by 7307 and fed to Pin 50 of 7651, Audio Processor.
Two Aux signals from the Rear Jack Panel and one channel
from the Side Jack Panel can be fed to the switch inside the
IC. A single channel audio signal from the PIP/DW Panel is
fed to the IC on Pin 47. The Audio Processor is capable of
processing all analog TV standards worldwide, as well as the
NICAM digital standard. In the Auto mode, the IC is capable
of automatically detecting the Audio standard. An AVC
(Automatic Volume Correction) circuit in the IC corrects for
changes in audio levels from different program sources.
When the AVC circuit turned On, a fixed output of -18 dB will
be maintained for an input varying from -24 dB to 0 dB. That
is with an input level of 0 dB being 2 volts rms and the output
level of 0 dB being 1.4 volts rms. Pins 21 and 20 are the
outputs to the Audio Amplifier. Pins 18 and 17 are output to
the Headphone Amplifier while Pin 23 is a line level output for
a Subwoofer. The Subwoofer channel is developed by
combining the Left and Right Audio channels and sending it
through a Low Pass Filter. The Audio Amplifier, Headphone,
and Subwoofer are all tied to an internal volume control. The
SC1_OUT_R and SC1-OUT-L are fixed line level outputs,
which are fed to the Audio Output on the Rear Jack Panel.
The Aux out, Headphone, or Speaker output can be driven by
different sources as selected by the user. For example, the
user can be listening to the Audio from the main picture
through the speakers and listening to the PIP Audio through
the Headphones.
Audio from 7651 on the SSB Panel is fed to the Audio
Amplifier on the SSM Panel. The Audio is input on Pins 7 and
11 and output on Pins 4 and 2. The IC is powered by a 40
volt AMP-VCC supply from the Full Power Supply. When the
set is turned off, the Standby line goes high causing Pin 5 of
7402 to be approximately 40 volts. This shuts the Amplifier
completely off, preventing a POP in the speakers. When the
set is turned On, the Standby line is High, turning 7405 Off,
switching 7410 On. The Sound-Enable line is High, turning
7401 On. Pin 5 of 7402 will then be approximately 32 volts.
Audio will be present on the output of 7402. If the user
presses the Mute button, the Sound-Enable line will go low
causing 7401 to turn off. Pin 5 of 7402 will then go to
approximately 36 volts, muting the output.
The output of the Amplifier is fed to a Center Amp Switch
Panel. When the switch is in the internal position, Left and
Right Audio is routed to the internal speakers. In the External
position, the Left and Right Internal speakers are connected
in series with the Center Amp Input on connector 1000.
Left and Right Headphone Audio is fed to 7403 and then to
the Headphone Jack on the Side Jack Panel. Sub-woofer
audio is buffered by 7415 before being fed to the Rear Jack
Panel.
9.10 Microprocessor
The Microprocessor (Painter), 7064, is located on the SSB
Panel. The User communicates with the Microprocessor via
the Remote Control or the Front Keyboard. The Keyboard is
a resistor latter which produces a voltage level change on Pin
5 when the User makes a selection. The Remote Receiver
is located on the Front Panel. The Program to run the set is
loaded in the ROM in the Microprocessor. User settings,
Geometry settings, Options Codes to identify the set, Error
Codes, Tuner and Audio settings, and Cutoff settings are
Figure 9-22
CL 06532143_029.eps
081100
stored in the Memory IC 7066. The Microprocessor
communicates with the Memory IC via an I2C buss. The
Microprocessor communicates with the rest of the set via to
I2C busses on Pins 82, 81, and 84, 83. Additional
communications with the set is done through six analog
control lines, STAND-BY, SEL-MAIN-FRNT-RR, SEL-MAINR1R2, SOUND-ENABLE, SYS1 AND SYS2. The STANDBY line goes Low to turn the set on. On Screen Display
(OSD) is output on Pins 46, 47, and 48 of the IC. Sync for
this display is input on Pins 53 and 55.
Page 32
GB 98A10PTV2.0 NTSC9.
Circuit Description
9.11 Board Level Troubleshooting
Before proceedingwith Component Level repair, the problem
must first be localized to the Panel. If Power is applied to the
set and the Mains Switch is turned on, the 3.3-volt and 5 volt
Standby supplies should be present on connector 1518 on
the Large Signal Panel. The 3.3-volt supply is located on Pin
10 and the 5-volt supply is located on Pin 12. If these
supplies are present, the Standby Power Supply on the
Large Signal Panel is working. In the Standby Mode, the
Standby Line on Pin 9 of 1518 should be High. When the set
is turned on, this line should go low. If this line goes low, the
130-volt supply should appear on Pin 2 of 1518. In addition
the 5.2-volt, -32 volt, and +32 volt supplies should all appear.
If they do not appear, check the Main B+ on Pin 3 of 1500.
The Main and Standby B+ from the Power Factor Correction
Panel is separate. It is possible to have one and not the
other. If the Standby line goes low, and the Main B+ is
present, the Large Signal Panel should be repaired or
replaced. The Large Signal Panel has the Power Supplies,
High Voltage, Line and Frame Drive circuits. The SSM Panel
has the Jack Panel, SSB interface, CRT Drive, Convergence,
and Audio output circuits. The SSB Panel which plugs into
the SSM Panel has the Microprocessor, IF, Video, and Audio
processing circuits. The PIP Panel has the Picture in Picture
and Double Window circuits along with a second Tuner.
algorithm that installs TV sets
directly from cable network by
means of a predefined TXT page
ADCAnalogue Digital Converter
AFCAutomatic Frequency Control:
control signal used to tune to the
correct frequency
AGCAutomatic Gain Control: algorithm
that controls the video input of the
feature box
AMAmplitude Modulation
ARAspect Ratio: 4 by 3 or 16 by 9
ArtisticSee Painter 2.5: main processor
AVLAutomatic Volume Level
BGSystem B and G
BLKINBlack current information
B-SC1-INBlue AV1 in
B-SC2-INBlue AV2 in
B-TXTBlue teletext
BOCMABiMOS one Chip Mid-end
Architecture
BTSCBroadcast Television Standard
Committee (sound)
C-FRONTChrominance front input
CLConstant Level: audio output to
connect with an external amplifier
CompairComputer aided rePair
CRTCathode Ray Tube, or picture tube
CSMCustomer Service Mode
CTIColor Transient Improvement:
manipulates steepness of chroma
transients
CVBSComposite Video Blanking and
Synchronization
CVBS-AVCVBS signal from external source
(VCR, VCD, etc.)
CVBS-INTCVBS signal from Tuner
CVBS-MONCVBS monitor signal
CVBS-TER-OUTCVBS terrestrial out
DBXDynamic Bass eXpander
DFUDirections For Use; owner’s manual
DNRDigital Noise Reduction: noise
reduction feature
DSPDigital Signal Processing
DSTDealer Service Tool: special remote
control designed for dealers to enter
service mode
DVDDigital Video Disc
DYN-PHASECORRDynamic phase correction
EHTExtra High Tension
EHT-INFOExtra High Tension information
EPGElectronic Program Guide: system
used by broadcasters to transmit TV
guide information (NexTView)
EWEast West, related to horizontal
deflection of the set
AVExternal (source), entering the set
via AV or via cinches
FBLFast Blanking: DC signal
accompanying RGB signals
FBL-SC1-INFast blanking signal for AV1 in
FBL-SC2-INFast blanking signal for AV2 in
FBL-TXTFast Blanking Teletext
FILFilament supply voltage
FMField Memory or Frequency
(SVHS)
G-SC1-INGreen AV1 in
G-SC2-INGreen AV2 in
G-TXTGreen teletext
HAHorizontal Acquisition: horizontal
sync pulse coming out of the
BOCMA
HFBHorizontal Flyback Pulse: horizontal
sync pulse from large signal
deflection
BOCMAHigh-end video Input Processor:
video and chroma decoder of A10
HPHeadphone
InterlacedScan mode where two fields are
used to form one frame. Each field
contains half the number of the total
amount of lines. The fields are
written in “pairs”, causing line flicker.
IO-BUSIn/Out - Bus
Last StatusThe settings last chosen by the
customer and read and stored in
RAM or in the NVM. They are called
at start-up of the set to configure the
set.
LATAMLATin AMerican countries (Brazil,
Argentina, etc.)
LEDLight Emitting Diode
LINE-DRIVELine drive signal
LSPLarge signal panel
MSPMultistandard Sound Processor: ITT
sound decoder of A10
MUTEMute-Line
NAFTANorth American Free Trade
Agreement countries (Canada, USA
and Mexico).
NCNot Connected
NICAMNear Instantaneously Companded
Audio Multiplexing
NVMNon Volatile Memory: IC containing
TV related data e.g. alignments
O/COpen Circuit
ON/OFF LEDOn/Off control signal for the LED
OSDOn Screen Display
PainterOn Screen Display, Teletext and
Control; also named Artistic
(SAA5565)
P50Project 50 communication: protocol
between TV and peripherals
PCBPrinted Circuit board
PTPPicture Tube Panel
RAMRandom Access Memory
RCRemote Control
RC5RC5 signal from the remote control
receiver
RESETReset signal
ROMRead Only Memory
SAMService Alignment Mode
SAPSecond Audio Program
SCSandcastle: pulse derived from sync
signals
SCAVEMScan Velocity Modulation
S/CShort Circuitr
SC1-OUTAV output of the MSP audio IC
SC2-B-INAV2 Blue in
SC2-C-INAV2 chrominance in
SC2-OUTAV output of the MSP audio IC
SIFSound Intermediate Frequency
SIMM80-fold connector between LSP and
SSB
SNDL-SC1-INSound left AV1 in
SNDL-SC1-OUTSound left AV1 out
SNDL-SC2-INSound left AV2 in
SNDL-SC2-OUTSound left AV2 out
SNDR-SC1-INSound right AV1 in
Page 34
GB 100A10PTV2.0 NTSC9.
SNDR-SC1-OUTSound right AV1 out
SNDR-SC2-INSound right AV2 out
SNDR-SC2-OUTSound right AV2 out
SNDS-VL-OUTSurround sound left variable level
out
SNDS-VR-OUTSurround sound right variable level
out
SNERTSynchronous No parity Eight bit
Reception and Transmit
SSBSmall Signal Board
STBYStandby
SWSubwoofer
TXTTeletext
Pmicroprocessor
VAVertical Acquisition
V-BATMain supply for deflection
VFBVertical Flyback Pulse: vertical sync
pulse coming from the feature box
VLVariable Level out: processed audio
output towards external amplifier
WYSIWYRWhat You See Is What You Record:
record selection that follows main
picture and sound
XTALQuartz crystal
Y-OUTLuminance signal
Circuit Description
Page 35
10. Spare Parts List
Spare Parts List
GB 101A10PTV2.0 NTSC10.
General
Various
1110 3135 017 04961 CRT Panel Red
1120 3135 017 04961 CRT Panel Blue
1130 3135 017 04981 CRT Panel Green
1140 3135 017 05341 SCAN VELOCITY
1160 3135 017 05541 REAR SWITCH PANEL
1170 3135 017 05461 SIDE JACK PANEL
1180 3135 017 05001 MAINS SWITCH PANEL
1190 3135 017 05121 ASSY A10 SSM NTSC AP
0102 3135 011 03271 IC-SPRING
0106 3135 011 03271 IC-SPRING
1801 2412 020 00724 CON BM V 2P M 2.50 EH B
1802 2412 020 00724 CON BM V 2P M 2.50 EH B
1803 2412 020 00724 CON BM V 2P M 2.50 EH B
1804 4822 267 10557 B10B-EH-A