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SM - 96004
Service Manual
Colour Television
TX-21AD2
EURO-2 Chassis
Specifications
Power Source : 220-240V AC 50Hz AV2 OUT Video (21 pin ) 1V p-p 75W
Power Consumption : 80W Audio (21 pin ) 500mV rms, 1kW
Aerial Impedance : 75W unbalanced, Coaxial Type AV3 IN Audio (RCA x 2)500 rms,10k
mV W
Receiving System : PAL I, PAL 60, Video (RCA x 1)1V p-p 75
W
Receiving Channels : UHF E21 - E69 High Voltage : 27kV _1kV at zero beam current
Intermediate Frequency :
Picture Tube : 51 cmV measured diagonally.
Audio Output :
Video 39.5 MHz
Internal Speaker 2 x 20W (Music Power)
Sound 33.5 MHz
8W Impedance
Colour 35.07 MHz
Headphones 8 W Impedance
Video / Audio
Terminals : Accessories supplied : Remote Control
UM3 Battery
AUDIO MONITOR OUT Audio(RCA x 2) 500mV rms,1k W
T.V. Stand
AV1 IN Video (21 pin ) 1V p-p 75W
Dimensions : Height : 465mm
Audio (21 pin ) 500mV rms,10k
W
Width : 558mm
RGB (21 pin )
Depth : 495mm
AV1 OUT Video (21 pin ) 1V p-p 75W Net Weight 23kg
Audio (21 pin ) 500mV rms, 1kW
AV2 IN Video (21 pin ) 1V p-p 75W Specifications are subject to change without notice.
Audio (21 pin ) 500mV rms,10 k W Weight and dimensions shown are approximate.
S-Video IN Y : 1V p-p 75W
NOTE : This service manual should be used in conjunction
(21 pin ) C : 0.3V p-p 75W
with the EURO 2 technical guide.
Panasonic Panasonic CS (UK)
WILLOUGHBY ROAD,
BRACKNELL
BERKS,
RG12 8FT.
Contents
Safety Precautions 2
Location of Controls 3
Chassis Service Position 4
Service Mode 5
Self Check 6
Adjustment Procedure 6
Alignment Settings 7
Waveform Pattern Table 8
Block Diagrams 9
P.C.B. Views 12
Schematic Diagrams 14
Parts Location 17
Replacement Parts List 18
Safety Precautions
General Guide Lines
1. It is advisable to insert an isolation transformer in the AC suply
p 4. Check each exposed Metallic part and check the voltage at each
before servicing a hot chassis. point.
2. When servicing, observe the original lead dress in the high 5. Reverse the AC plug at the outlet andrepeat each of the above
voltage circuits. If a short circuit is found, replace all parts which measurements.
have been overheated or damaged by the short circuit. 6. The potential at any point should not exceed 1.4Vrms. In case a
3. After servicing, see that all the protective devices such as measurement is outside the limits specified, there is a possibility
insulation barriers, insulation papers, shields and isolation R-C of a shock hazard, and the receiver should be repaired and
combinations are correctly installed. rechecked before it is returned to the customer.
4. When the receiver is not being used for a long period of time,
unplug the power cord from the AC outlet. HOT CHECK CIRCUIT
5. Potentials as high as 28kV are present when this receiver is in
operation. Operation of the receiver without the rear cover A.C. Voltmeter
involves the danger of a shock hazard from the receiver power
supply. Servicing should not be attempted by anyone who is not
familiar with the precautions necessary when working on high
voltage equipment. Always discharge the anode of the picture to
the chassis before handling the tube.
6. After servicing make the following leakage current checks to
prevent the customer from being exposed to shock hazards. Water Pipe
To Instrument's (Earth)
Leakage Current Cold Check exposed
metallic parts 2K ohm 10W
1. Unplug the AC cord and connect a jumper between the two Fig.1
prongs of the plug.
2. Turn on the receiver's power switch. X-Radiation Warning
3. Measure the resistance value with an ohmmeter, between the
jumpered AC plug and each exposed metallic cabinet part on the 1. The potential sources of X-Radiation in TV sets are the high
receiver, such as screw heads, aerials , connectors, control voltage section and the picture tube.
shafts etc. When the exposed metallic part has a return path to 2. When using a picture tube test jig for service ensure that the jig
the chassis the reading should be between 4M ohm and 20M is capable of handling 28kV without causing X-Radiation.
ohm. When the exposed metal does not have a return path to NOTE : It is important to use an accurate periodically calibrated high
the chassis the reading must be infinite. voltage meter
Leakage Current Hot Check 1. Set the brightness to minimum.
2. Measure the high voltage. The meter should indicate 27kV _1kV
1. Plug the AC cord directly into the AC outlet. Do not use an at zero beam current if the meter indication is out of tolerance,
isolation transformer for this check. immediate service and correction is required to prevent the
2. Connect a 2k ohm 10W resistor in series with an exposed possibility of premature component failure.
metallic part on the receiver and an earth such as a water pipe. 3. To prevent an X-Radiation possibility, it is essential to use the
3. Use an AC voltmeter with high impedance to measure the specified tube.
potential across the resistor.
Location Of Controls
FOCUS
SCREEN
Fig.2
Service Hints
How to remove the rear cover
i. Remove the 5 fixing screws (A) as shown in Fig.3/Fig.4.
SCREW
Fig.4
SCREWS (A)
Fig.3.
How to move the chassis into the Service position
NOTE: To place the chassis into the advised service position the T.V. must be on the T.V. stand provided with the set.
1. To place the chassis into service position hold and lift the rear of the E-PCB chassis and gently pull the chassis toward you as shown in Fig.5.
B-PCB service position.
i. Release the respective wiring clips and rotate the chassis horizontally through anti-clockwise, then lift the front of the chassis as shown in
90_
Fig.6.
ii. Insert the beadclamper located in the bottom left hand corner of the cabinet (Fig.8.) into the chassis frame shown in Fig.9.
iii. After servicing ensure all wiring is returned to its original position before returning the receiver to the customer.
E-PCB service position.
i. Release the respective wiring clips and rotate the chassis horizontally through 180_ anti-clockwise, the lift the FBT side of the chassis as shown
in Fig.7.
ii. Insert the beadclamper located in the bottom left hand corner of the cabinet (Fig.8.) into the chassis frame shown in Fig.9
iii. After servicing ensure all wiring is returned to its original position before returning the receiver to the customer.
Fig.5
CABINET
E - PCB
BEAD
CLAMPER
B - PCB E - PCB
Fig.8.
MAINS
SWITCH
INSERT
BEAD
CHASSIS CLAMPER
FRAME B - PCB
T.V. STAND
T.V. STAND
Fig.6. Fig.7.
Fig.9.
.
4
TX-21AD2
Service Mode
The remote control is used for entering and storing adjustments, with the exception of cut-off adjustments which must always be done prior to service
adjustment. Perform adjustments in accordance with screen display. The display on the screen also specifies the CCU variants as well as the approx.
setting values. The adjustment sequence for the service mode is indicated below.
1. Set the Bass to maximum position, set the Treble to minimum 3. Press the YELLOW / BLUE buttons to alter the function values.
position, press the F button followed by the Volume down on the 4. Press the STORE button on the preset panel after each
customer controls at the front of the TV and at the same time adjustment has been made to store the required values.
press the Reveal button on the remote control, this will place the
5. To exit the Service Mode press the Normalisation button.
TV into the Service Mode.
2. Press the RED / GREEN buttons to step down / up through the
functions.
NOTE: This TV also has the option of using a Memory Pack which enables you to copy the
preset TV channels and analogue levels into the Memory
Pack and then upload them onto another EURO-2 TV set.
Using the Memory Pack
TV to Memory Pack process 1. Plug the memory pack into the lower of the two 21 pin terminals
1. Plug the memory pa into the lower of the two 21 pin terminals
ck at the back of the TV and switch the TV on. If the TV has only
at the back of the TV and switch the TV on. If the TV has only one 21 pin connector then this will be able to accept the memory
one 21 pin connector then this will be able to accept the memory pack.
pack. 2. Go into the Service Mode as explained above. The screen will
2. Go into the Service Mode as explained above. The screen will show:-
show:- Program 3. Press the STORE button
Program 3. Press the blue button on External>>TV on the TV. The screen will
External>>TV the remote control. The show:-
screen will show:-
Loading
Program 4. Press the STORE button
TV>>External on the TV. The screen will
show:- 4. All the tuning information stored inside the Memory Pack will
now be transferred to the TV. This process will take 2-3 minutes
Storing
to complete and when finished the screen will show:-
OK!
5. All the tuning information stored inside the TV will now be
transferred to the Memory Pack. This process will take 2-3
minutes to complete and when finished the screen will show:- 5. The tuning information from the Memory Pack has now been
copied into the TV
OK!
6. To exit from the Service Mode switch off the TV.
7. The process has now been completed and the Memory Pack
Memory Pack to TV Process can now be removed.
Errors
If an error occurs while using the Memory Pack the TV will detect this and the screen will show:-
Program
Error!
If this happens then switch off the TV and repeat the process that was being used. If the errors continue to occur then check the connectors between
the TV and the memory pack and check the 9V battery inside the memory pack.
5
TX-21AD2
SELF CHECK
Self check is used to automatically check the Bus lines and Hexadecimal code of the TV set.
To enter the Self Check mode press Function down button, on the
Preset Panel, at the same time pressing the Status button, on the Remote Control,
and the screen will show:-
Dolby IC
1 ok Tuner 11 -- for C/R 21 ok P SBLED
VIF P S MODE ok P OFF
2 ok 12 ok 22
3 ok EEPROM 13 ok P. TA0 ok
23 P DEFL
Sound AV
4 -- switch1
14 ok P. TA1 24 ok P RAM
Video AV ok
5 ok switch1 15 P. TA2
Hex codes
6 ok VDP 16 ok P. TA3
7 ok TPU 17 ok P SDA 06
ok MSP P CE
8 18 ok
SCL1
34
9 -- Dolby Sub 19 ok P SCL 3
94
10 -- Dolby IC P SCL4
for L/R
20 ok
85
If the CCU ports have been checked and found to be incorrect then "--" will appear in place of "OK".
Adjustment Procedure
Item/Preparation Adjustments
+B SET-UP 1. Set the +B voltage up as follows:
1. Receive a window pattern Adjust R811 so that B2 shows 130V +/- 1V
2. Set the controls: 2. Confirm the following voltages.
Brightness minimum
Contrast minimum B1 200 +/- 10V B6 12 +/- 0.5V
Volume minimum B3 27 +/- 1V B7 5 + 0.1/-0.25V
B4 41.0 +/- 1V B8 5 +/- 0.25V
B5 15.5 +/- 1V U33 31 +/- 1V
RF AGC
1. Receive a test pattern. 1. Check that the noise becomes large when the RF AGC VR
2. Connect an oscilloscope between the tuner R126 is turned counterclockwise. After the check turn it clockwise.
RF AGC and ground. 2. Gradually turn the RF AGC VR anti-clockwise, and set the
3. Set the oscilloscope gain range to 1V/div. RF AGC VR to the point where the RF AGC voltage is just falling to a
point where this voltage drops by 0.2V from e maximum value.
th
CUT OFF
1. Receive a window pattern. 1. Confirm then value is 128 and select Ug2 mode noting colour with
2. Degauss the tube externally. largest value
3. Set the TV into Service Mode 1. 2. Turn the screen VR until a colour reaches 20~30.
4. Select Cutoff DC mode. 3. Connect an oscilloscope to the cathode with the biggest value
colour.
4. Select Cutoff DC mode and adjust Cutoff pulse to 159V +/- 5V.
5. Disconnect the oscilloscope and adjust the screen to whichever colour
reaches 70 +/- 30 first.
6
TX-21AD2
Alignment Settings (The figures used below are nominal and used for representative purposes only)
Alignment Function TX-21AD2 Settings / Special features
1. Vertical amplitude V-AMP Optimum setting
063
2. Vertical symmetry V-SYM Optimum setting
002
3. Vertical linearity V-LIN Optimum setting
-020
4. Vert. D.C. Vert. D.C. No Adjustment
000
5. V-Pos. V. Pos Optimum setting
005
6. Horizontal amplitude H-AMP Optimum setting
-044
7. Horizontal position H-POS Optimum setting
542
8. Text Position TEXT POSITION Optimum setting
049
9. EW-amplitude E-W AMP 1 Optimum setting
-059
10. EW-amplitude E-W AMP 2 Optimum setting
044
11. Trapezium-comp TRAPEZ 1 Optimum setting
000
12. Trapezium- comp TRAPEZ 2 Optimum setting
-009
13. Colour VCO Colour VCO Press either Blue or Yellow buttons to effect
006 automatic adjustment
14. Cut-off DC Cut-off DC No Adjustment
050
Select Cutoff DC in Service Mode mode and
confirm the value is 128. Select 2 Test noting
Ug
colour with largest value, adjust on FBT until a
Ug 2 Test colour reaches 20 ~ 30. Connect an
15. Ug2 Test 094 044 020 oscilloscope to the cathode of the biggest value
colour, selectCutoff DC mode and adjust get
Cutoff pulse voltage to 159_5V. Disconnect the
oscilloscope and adjust the screen to whichever
colour reaches 70_30 first.
16. Cutoff Cutoff Press the GREEN button to step through the
057 064 056 settings. Adjust for optimum.
17. White White Press the GREEN button to step through the
200 255 246 settings. Adjust for optimum.
7
PIN 42 PIN 6 E8 PIN 5 E8 PIN 3 E8
I601
10u 50u sec/div 10u 10u
PIN 4 E8 PIN 44 PIN 7 PIN 18
10u 10u 2u sec/div 5u sec/div
(Chroma)
PIN 3 PIN 6 PIN 34
PIN 6 IC801
5u sec/div 5m sec/div 5m sec/div
5m sec/div
COLLECTOR BASE Q503 PIN 7 BASE
64u sec/div 20u sec/div 5m sec/div 20u sec/div
PIN 5 BLUE DRIVE
PIN 8 PIN 1
IC701 EMITTER Q353
64u sec/div 5m sec/div 120v
5m sec/div
RED DRIVE GREEN DRIVE
EMITTER EMITTER Q352
Q351 80v 100v
X103 5
TUNER
FILTER
6 IC102
VIDEO
AGC
Q103
10 21
BUFFER
J Q3006 1
V 16
K 19 TUNER
BUFFER
3 VIDEO IN
11 1 V
20 5
15 0
1
Q3001 V/Y IC3001
AV1 17
BUFFER AV
J V/Y Q3005
V
K 19 14 BUFFER
3 10 8 11 13
0 C
15
0 V/Y
20 C
1
Q3004
AV2
BUFFER IC3501
MEMORY
J 44 39 D 17
Y WE
K 42 3 38 2
/R RAS
3 31 16 37 3
V/Y P0 CAS
1 4 15 36 16
P1 A0
0 3 14 35 5
C1 A1
2 IC601 12 12 34 6
AV3 C0 33 A2 7
VIDEO 13 9
Y0 IC3502 A3
19 6 32 8
Y1 TELETEX A4
20 7 31 12
R Y2 A5
64 21 8 30 11
G MSY A6
32 20 29 10
63 A7
B 28 13
61 55 57 59 27 A8 14
27
26 A9 15
25 4
A10
H OUT
R
Q302 Q307 Q301 Q351
AMP BUFFER AMP OUTPUT AMP
1 9
G IC351
Q304 Q308 Q303 Q352
2 RGB AMPS 8
AMP BUFFER AMP OUTPUT
3 7
B
Q306 Q309 Q305 Q353
AMP BUFFER AMP OUTPUT
MUTE SIGNAL
LEFT AUDIO
IC102
X103 Q102 Q101 RIGHT AUDIO
TUNER 8 SIF/VIF/DEMODULATOR
FILTER BUFFER AMP
22 IF SIGNAL
SIF
Q202 Q201
AMP BUFFER
L
6 R L
W
1 58 R R 1 13
R 50 28 Q2102 6
SIF
2 2 AV1 IN
BUFFER
1
49 IN
2 L I251
1 3 34 AV1 OUT
AUDIO OUTPUT
AV1 33
1 R L L AMP
IC2101 Q2101
29 3
L AUDIO BUFFER
52
R AV2 IN PROCESSOR
53
L
L 37
R
6 36 AV2 OUT
W L
46
1 R 25 5 26 4
47
2 2 R
2 L AV3 IN
1 3
AV2 AV2 OUT Q2310 Q2309 Q2306 Q251 Q252
1 R
BUFFER BUFFER MUTE MUTE MUTE
L
6 Q2305
W
R Q2306 MUTE
1
2 2 MUTE
1 L Q2302 Q2301 Q2308
1 3 Q2307
AMP AMP MUTE
AV3 R MUTE
1 Q2305
MUTE
D3018 D3019
R
Q1208
J
K MUTE
2 L
3
0
1
IC701
HORIZ OUTPUT
IC851 IC102 IC2301 IC103 12V
12V IF PROCESSOR 8V REG 12V REG
8V IC1202
5VSB
IC451 EEPROM
VERTICAL MEMORY
12V
27V
IC601
VIDEO
TUNER
29V
I466
AUDIO OUTPUT
IC2101
SOUND PROCESSOR
200V
Y
FBT IC3001
PCB
AV
D554 SWITCHING
Q551
Q503
LINE
DRIVER
OUTPUT
27V
IC1203
IC1201
EAROM
MICROPROCESSOR
PROGRAMME
CONTROL 5V
MEMORY
29V 15V 27V 150V 5V 5VSB
5V RESET
IC1205
RESET
D854 D852 D851 D855
T801
CLOCK 4
Q851
DATA
D853
IC801 CLOCK
PSU IC3501
IC3502
CONTROL TEXT
5V TELETEX
MEMORY
D1204
IC1206
T1201
5V
TP'S TRANS
TPY1 C2 Q351 C2
TPY2 C3 Q352 C2
TPY3 C2 Q353 C2
TPY4 B2
TPY5 B2 IC'S
TPY6 A3 IC351 B3
Y BOARD TNP117069
SCHEMATIC DIAGRAM FOR MODELS
TX-21AD2
(EURO-2S CHASSIS)
IMPORTANT SAFETY NOTICE
Components identified by mark have special characteristics
important for safety. When replacing any of these components,
use only manufacturer's specified parts.
Notes
i. RESISTOR
All resistors are carbon