Panasonic PT-52DL52, Service Manual

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follows:
B+ line Minimum
Resistance
+31.2 ± 1.5V (PA-Board : L844) 10k
+17.5 ± 1.5V (PA-Board : L854) 10k
-17.5 ± 1.5V (PA-Board : L853) 10k
+2.5 ± 0.5V (DG-Board :
TP9101) 1k
+3.3 ± 0.5V (DG-Board :
TP9102) 1k
+3.3 ± 0.5V (DG-Board :
TP9104) 1k
+2.5 ± 0.5V (DG-Board :
TP9105) 1k
5. When the set is not used for a long period of time, unplug the AC
power cord plug from the AC line outlet.
6. After servicing make the following leakage current checks to
prevent the customer from dangerous electrical shock.
1.2. Leakage Current Cold Check
1. Unplug the AC power cord and short between the two prongs of
the AC plug with a jumper wire.
2. Set the power switch of this set to ON position.
3. Measure the resistance value with an ohmmeter between the
shorted AC plug and each exposed metallic part of the set cabinet
such as screwheads, connectors, and control shafts. When the
exposed metallic part has a return path to the chassis,the reading
should be more than 4 M .
When the exposed metal part does not have a return path to the
chassis, the reading must be infinity.
1.3. Leakage Current Hot Check (See Fig. 1 )
1. Plug the AC power cord directly into the AC line outlet. Do not use
an isolation transformer for this check.
2. Connect the measuring circuit as shown in Fig. 1 . between each
exposed metallic part of the set and an earth ground such as a
water pipe.
4