Service manual [PDF] (28 pages)
- Updated: 30.04.2026
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Power Source :
AC AUTO 110-240V, 50/60 Hz
Power Consumption :
83W
Aerial Impedance :
75Ω unbalanced
Coaxial type
Receiving Channels :
VHF
2-13 (USA STANDARD)
CATV
1-125 (USA STANDARD)
UHF
14-69 (USA STANDARD)
Intermediate Frequency :
Video
38.0 MHz
Sound
31.5 MHz (D, K, K1)
32 MHz (I)
32.5 MHz (B, G)
33.5 MHz (M)
Colour
33.57 MHz (PAL)
33.6 MHz (SECAM)
33.75 MHz (SECAM)
34.42 MHz (NTSC)
© 2005 Matsushita Electric Industrial Co., Ltd. All
rights
reserved.
Unauthorized
copying
and
distribution is a violation of law.
TC-21FG10P
GP31 Chassis
Video / Terminals :
AV1, 2
RAV In
Video In 1 Vp-p 75Ω
Audio In Approx. 400mVrms
Monitor Out
Video Out 1 Vp-p 75Ω
Audio Out Approx. 400mVrms
High Voltage :
27.5kV±1.5
at zero beam current
Picture Tube :
A51LXR195X
51cm (21 inches)
Measured diagonally,
90° deflection
Audio Output :
16.0W
Dimensions :
Height : 473 mm
Width : 648 mm
Depth : 488 mm
Mass :
24 kg (Net Wt.)
Specifications are subject to change without notice.
Mass and dimensions shown are approximate.
Colour Television
Specifications
ORDER NO. MTV0501395C3
1 Safety Precautions
3
1.1. General Guide Lines
3
1.2. Leakage Current Cold Check
3
1.3. Leakage Current Hot Check (Fig. 1)
3
1.4. X-Radiation
3
1.5. GP31 Chassis Block Diagram
4
2 Service Hints
5
2.1. Service Position for E-Board
5
2.2. Factory Mode Adjustment
5
2.3. Adjustment for White Balance
6
2.4. Adjustment for CRT CUT OFF
6
2.5. Adjustment Procedure
7
2.6. PAL Colour
8
2.7. Adjustment
8
3 Conductor Views
12
4 Schematic Diagram
13
4.1. A Board
15
4.2. L Board
20
5 Parts Locations
23
6 Replacement Parts List
24
6.1. Replacement Parts List
25
CONTENTS
Page
Page
2
1 Safety Precautions
1.1.
General Guide Lines
1. It is advisable to insert an isolation transformer in the AC supply before servicing this hot chassis.
2. When servicing, observe the original lead dress, especially the lead dress in the high voltage circuits. If a short circuit is found,
replace all parts which have been overheated or damaged by the short circuit.
3. After servicing, see to it that all the protective devices such as insulation barriers, insulation papers, shields and isolation R-C
combinations, are properly installed.
4. When the receiver is not to be used for a long period of time, unplug the power cord from the AC cord outlet.
5. Potential, as high as 29.0kV is 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
thoroughly familiar with the precautions necessary when working on high voltage equipment. Always discharge the anode of the
picture tube to the receiver chassis before handling the tube. After servicing make the following leakage current checks to
prevent the customer from being exposed to shock hazards.
1.2.
Leakage Current Cold Check
1. Unplug the AC cord and connect a jumper between the two prongs on the plug.
2. Turn on the receiver’s power switch.
Measure the resistance value, with an ohmmeter, between the jumper AC 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 4 MΩ and 20 MΩ. When the exposed metal does not have a return path to the chassis,
the reading must be infinite.
1.3.
Leakage Current Hot Check (Fig. 1)
1. Plug the AC cord directly into the AC outlet. Do not use an isolation transformer for this check.
2. Check a 2 kΩ non-inductive resistor and an AC/DC current meter, in series with each exposed metallic part on the receiver in
turn and an earth such as a water pipe.
The current from any point should not exceed 0.7 mA peak AC or 2 mA DC. In the case of a measurement being outside of
these limits specified, there is a possibility of a shock hazard and the receiver should be repaired and rechecked before it is
returned to the customer.
Fig. 1
,
1.4.
X-Radiation
Warning:
The potential sources of X-Radiation in TV set are the EHT section and the picture tube. When using a picture tube test jig for
service, ensure that jig is capable of handling 29.0kV without causing X-Radiation.
Note: It is important to use an accurate periodically calibrated high voltage meter.
1. Set the brightness to minimum.
2. Use the remocon to get into Service Mode.
3. Measure the EHT. The meter reading should indicate 27.5±1.5kV. If the meter indication is out of tolerance, immediate service
and correction is required to prevent the possibility of premature component failure.
4. To prevent the possibility X-Radiation, it is essential to use the specified picture tube, if service replacement becomes
necessary.
3
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