Panasonic TX-28PL10P Service Manual ▷ View online
Colour Television
TX-28PL10P
EURO- 4H Chassis
SPECIFICATIONS
Power Source:
220-240V a.c., 50Hz
Power Consumption:
124W
Stand-by Power
Consumption:
Consumption:
1,4W
Aerial Impedance:
75
Ω unbalanced, Coaxial Type
Receiving System:
PAL B/G, H, D/K, PAL-525/60
SECAM B/G, D/K
M.NTSC (AV only)
NTSC (AV only)
SECAM B/G, D/K
M.NTSC (AV only)
NTSC (AV only)
Receiving Channels:
VHF E2-E12
VHF E2-E12
VHF H1-H2 (ITALY)
VHF A-H (ITALY)
VHF R1-R2
VHF R3-R5
VHF R6-R12
UHF E21-E69
CATV (S01-S05)
CATV S1-S10 (M1-M10)
CATV S11-S20 (U1-U10)
CATV S21-S41 (HYPERBAND)
Intermediate Frequency:
Video/Audio
Video
Video/Audio
Video
38,9MHz
Audio
33,4MHz (B/G)
33,16MHz (A2 Stereo)
33,05MHz (NICAM)
32,4MHz (D/K)
32,66MHz (Czech Stereo)
33,16MHz (Polish Stereo)
33,16MHz (A2 Stereo)
33,05MHz (NICAM)
32,4MHz (D/K)
32,66MHz (Czech Stereo)
33,16MHz (Polish Stereo)
Colour
34,47MHz (PAL)
34,5MHz, 34,65MHz (SECAM)
34,5MHz, 34,65MHz (SECAM)
Terminals:
AUDIO MONITOR OUT
AUDIO MONITOR OUT
Audio (RCAx2) 500mV rms 1k
Ω
AV1 IN
Video (21 pin) 1V p-p 75
Ω
Audio (21 pin) 500mV rms 10k
Ω
RGB (21 pin)
0,7V p-p 75
Ω
AV1 OUT
Video (21 pin) 1V p-p 75
Ω
Audio (21 pin) 500mV rms 1k
Ω
AV2 IN
Video (21 pin)
1V p-p 75
Ω
Audio (21 pin)
500mV rms 10k
Ω
S-Video IN
Y: 1V p-p 75
Ω
(21-pin)
C:0,3V p-p 75
Ω
AV2 OUT
Video (21 pin)
1V p-p 75
Ω
Audio (21 pin)
500mV rms 1k
Ω
AV3 IN
S-Video IN
Y: 1V p-p 75
Ω
(4-pin)
C:0,3V p-p 75
Ω
Audio (RCAx2)
500mV rms 10k
Ω
Video (RCAx1)
1V p-p 75
Ω
High Voltage:
30,5kV
±1kV
Picture Tube:
W66EKT50X71
66cm
Audio Output:
2 x 7W RMS, 2 x 15W MPO
8
8
Ω Impedance
Headphones:
8
Ω Impedance
Accessories
supplied :
supplied :
Remote Control
2 x R6 (UM3) Batteries
2 x R6 (UM3) Batteries
Dimensions:
Height:
Height:
508,8mm
Width:
763,2mm
Depth:
512,2mm
Net weight:
42kg
Specifications are subject to change without notice.
Weights and dimensions shown are approximate.
Weights and dimensions shown are approximate.
NOTE: This Service Manual should be used in conjunction with
the EURO-4H Technical guide.
the EURO-4H Technical guide.
ORDER No. 01-SM-015
CONTENTS
SAFETY PRECAUTIONS..........................................................................................................................................................2
SERVICE HINTS .......................................................................................................................................................................3
SERVICE POSITION.................................................................................................................................................................4
ADJUSTMENT PROCEDURE AND SELF-CHECK ..................................................................................................................5
WAVEFORM PATTERN TABLE ...............................................................................................................................................6
ALIGNMENT SETTINGS...........................................................................................................................................................7
BLOCK DIAGRAMS ..................................................................................................................................................................8
PARTS LOCATION .................................................................................................................................................................12
REPLACEMENT PARTS LIST ................................................................................................................................................13
SCHEMATIC DIAGRAMS .......................................................................................................................................................24
CONDUCTOR VIEWS.............................................................................................................................................................32
SERVICE HINTS .......................................................................................................................................................................3
SERVICE POSITION.................................................................................................................................................................4
ADJUSTMENT PROCEDURE AND SELF-CHECK ..................................................................................................................5
WAVEFORM PATTERN TABLE ...............................................................................................................................................6
ALIGNMENT SETTINGS...........................................................................................................................................................7
BLOCK DIAGRAMS ..................................................................................................................................................................8
PARTS LOCATION .................................................................................................................................................................12
REPLACEMENT PARTS LIST ................................................................................................................................................13
SCHEMATIC DIAGRAMS .......................................................................................................................................................24
CONDUCTOR VIEWS.............................................................................................................................................................32
SAFETY PRECAUTION
GENERAL GUIDE LINES
1. It is advisable to insert an isolation transformer in the
a.c. supply before servicing a hot chassis.
2. When servicing, observe the original lead dress in the
high voltage circuits. If a short circuit is found, replace
all parts that have been overheated or damaged by
the short circuit.
all parts that have been overheated or damaged by
the short circuit.
3. After servicing, see that all the protective devices
such as insulation barriers, insulation papers, shields
and isolation R-C combinations are correctly
installed.
and isolation R-C combinations are correctly
installed.
4. When the receiver is not being used for a long period
of time, unplug the power cord from the a.c. outlet.
5. Potentials as high as 31,5kV are present when this
receiver is in operation. Operation of the receiver
without the rear cover 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 tube.
without the rear cover 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 tube.
6. After servicing make the following leakage current
checks to prevent the customer from being exposed
to shock hazard.
to shock hazard.
LEAKAGE CURRENT COLD CHECK
1. Unplug the a.c. cord and connect a jumper between
the two prongs of the plug.
2. Turn on the receiver’s power switch.
3. Measure the resistance value with an ohmmeter,
3. Measure the resistance value with an ohmmeter,
between the jumpered a.c. plug and each exposed
metallic cabinet part on the receiver, such as screw
heads, aerials, connectors, control shafts etc. When
the exposed metallic part has a return path to the
chassis, the reading should be between 4M ohm and
20M ohm. When the exposed metal does not have a
return path to the chassis, the reading must be
infinite.
metallic cabinet part on the receiver, such as screw
heads, aerials, connectors, control shafts etc. When
the exposed metallic part has a return path to the
chassis, the reading should be between 4M ohm and
20M ohm. When the exposed metal does not have a
return path to the chassis, the reading must be
infinite.
LEAKAGE CURRENT HOT CHECK
1. Plug the a.c. cord directly into the a.c. outlet. Do not
use an isolation transformer for this check.
2. Connect
a
2k
Ω 10W resistor in series with an
exposed metallic part on the receiver and an earth,
such as a water pipe.
such as a water pipe.
3. Use an a.c. voltmeter with high impedance to
measure the potential across the resistor.
4. Check each exposed metallic part and check the
voltage at each point.
5. Reverse the a.c. plug at the outlet and repeat each of
the previous measurements.
6. The potential at any point should not exceed
1,4 Vrms. In case a measurement is outside the limits
specified, there is a possibility of a shock hazard, and
specified, there is a possibility of a shock hazard, and
the receiver should be repaired and rechecked before
it is returned to the customer.
it is returned to the customer.
X-RADIATION WARNING
1. The potential sources of X-Radiation in TV sets are
the high voltage section and the picture tube.
2. When using a picture tube test jig for service, ensure
that the jig is capable of handling 31,5kV without
causing X-Radiation.
causing X-Radiation.
NOTE
: It is important to use an accurate periodically
calibrated high voltage meter.
1. Set the brightness to minimum.
2. Measure the high voltage. The meter should indicate:
1. Set the brightness to minimum.
2. Measure the high voltage. The meter should indicate:
30,5kV ± 1kV.
If the meter indication is out of tolerance, immediate
service and correction is required to prevent the
possibility of premature component failure.
service and correction is required to prevent the
possibility of premature component failure.
3. To prevent any X-Radiation possibility, it is essential
to use the specified tube.
HOT CHECK CIRCUIT
a.c. VOLTMETER
WATER PIPE
(EARTH)
TO INSTRUMENT'S EXPOSED
METALLIC PARTS
METALLIC PARTS
Fig. 1.
2kΩ
Ω
Ω
Ω 10 Watts
2
SERVICE HINTS
How to remove the rear cover
1. Remove the 10 screws as shown in
Fig.2.
LOCATION OF CONTROLS
Fig. 3
Fig. 2
SCREWS
SCREWS
3
M-Board
Y-Board
E-Board
F-Board
P-Board
Z-Board
Q-Board
Focus
Screen
HOW TO MOVE THE CHASSIS INTO SERVICE POSITION
1. Remove
2
screws
(A), as shown in
Fig.4.
, and remove speaker assembly.
2. Hold and lift the rear of the chassis and gently pull the chassis toward you, as shown in
Fig.4.
3. Release the respective wiring clips.
4. Elevate the chassis as shown in
Fig .5.
5. Using a speaker screw, screw the chassis frame into the top speaker fixing rib (B), as shown in
Fig.6
.
6. After servicing replace the speaker, and ensure all wiring is returned to its original position before returning the receiver
to the customer.
(B)
(A)
(A)
Fig.4
Fig.5
(B)
Fig.6.
4