Схема телевизора Panasonic TX 29AS10P EURO 4H CHASSIS

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SAFETY PRECAUTIONS..........................................................................................................................................................2SERVICE HINTS .......................................................................................................................................................................3SERVICE POSITION.................................................................................................................................................................4ADJUSTMENT PROCEDURE AND SELF-CHECK ..................................................................................................................5WAVEFORM PATTERN TABLE ...............................................................................................................................................6ALIGNMENT SETTINGS...........................................................................................................................................................7BLOCK DIAGRAMS ..................................................................................................................................................................8PARTS LOCATION .................................................................................................................................................................12REPLACEMENT PARTS LIST ................................................................................................................................................13SCHEMATIC DIAGRAMS .......................................................................................................................................................24CONDUCTOR VIEWS.............................................................................................................................................................30
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, replaceall parts that have been overheated or damaged bythe short circuit.
3. After servicing, see that all the protective devices
such as insulation barriers, insulation papers, shieldsand isolation R-C combinations are correctlyinstalled.
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 receiverwithout the rear cover involves the danger of a shockhazard from the receiver power supply. Servicingshould not be attempted by anyone who is notfamiliar with the precautions necessary when workingon high voltage equipment. Always discharge theanode of the tube.
6. After servicing make the following leakage current
checks to prevent the customer from being exposedto 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,
between the jumpered a.c. plug and each exposedmetallic cabinet part on the receiver, such as screwheads, aerials, connectors, control shafts etc. Whenthe exposed metallic part has a return path to thechassis, the reading should be between 4M ohm and20M ohm. When the exposed metal does not have areturn path to the chassis, the reading must beinfinite.
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
10W resistor in series with an
exposed metallic part on the receiver and an earth,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 limitsspecified, there is a possibility of a shock hazard, and
the receiver should be repaired and rechecked beforeit 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 withoutcausing X-Radiation.
: 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:
30,5kV ± 1kV.
If the meter indication is out of tolerance, immediateservice and correction is required to prevent thepossibility 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
TO INSTRUMENT'S EXPOSEDMETALLIC PARTS