6
3) Measuring the voltage drop across a resistor by means of a VOM or battery
operated AC voltmeter. The 'limit' indication is 0.75V so analog meters must
have an accurate low voltage scale. The SIMPSON'S 250 and SANWA SH-
63TRD are examples of passive VOMs that are suitable. Nearly all battery
operated digital multimeter that have a 2 VAC range are suitable.
(see Figure 2.)
1-4. Safety Check-Out
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:-
1) Check the area of your repair for unsoldered or poorly soldered
connections. Check the entire board surface for solder splashes and bridges.
2) Check the inter board wiring to ensure that no wires are pinched or
contact high-wattage resistors.
3)Check all control knobs, shields, covers, ground straps and mounting
hardware have been replaced. Be absolutely certain you have replaced all
the insulators.
4) Look for unauthorized replacement parts, particularly transistors that
were installed during a previous repair. Point them out to the customer and
recommend their replacement.
5) Look for parts which, though functioning show obvious signs of
deterioration. Point them out to the customer and recommend their
replacement.
6) Check the line cords for cracks and abrasion. Recommend the
replacement of any such line cord to the customer.
7) Check the antenna terminals, metal trim, metalized knobs, screws and all
other exposed metal parts for AC leakage. Check leakage test as described
next.
8. For safety reasons, repairing the Power board and/or Inverter board is
prohibited.
Figure 2. AC voltmeter to check AC leakage
Safety Notes
1-3. Caution About the Lithium Battery
1) Danger of explosion if battery is incorrectly replaced. Replace only with
the same or equivalent type.
2) Outer case broken battery should not contact to water.
1-5.Leakage Test
The AC leakage from any exposed metal part to earth ground and from all
exposed metal parts to any exposed metal part having a return to chassis must
not exceed 0.5mA (500 microamperes).
Leakage current can be measured by any one of the three methods:-
1) A commercial leakage tester such as the SIMPSON 229 or RCA WT540A.
Follow the manufacturers instructions to use those instructions.
2) A battery-operated AC milliampmeter The DATA PRECISION 245 digital
multimeter is suitable for this job.
1-6. How to Find a Good Earth Ground
1) A cold-water pipe is a guaranteed earth ground; the cover-plate retaining
screw on most AC outlet boxes is also at earth ground.
2) If the retaining screw is to be used as your earth ground, verify that it is at
ground by measuring the resistance between it and a cold-water pipe with an
ohmmeter. The reading should be zero ohms.
3) If a cold-water pipe is not accessible, connect a 60- to 100-watt trouble-
light (not a neon lamp) between the hot side of the receptacle and the
retaining screw. Try both slots, if necessary, to locate the hot side on the line;
the lamp should light at normal brilliance if the screw is at ground potential
(see Figure 3).
Figure 3. Checking for earth
ground.
Содержание KDL-50W7 C Series
Страница 2: ...LCD TV SERVICE MANUAL COMMON GN1G CHASSIS Segment XM A ...
Страница 14: ...BMX Board PWB A side Detail 3 3V 1 5V 5 0V C9224 F9016 C9222 F9015 C9216 C9213 R9321 F9013 C9188 R9277 C9185 ...
Страница 16: ...16 BMX Board PWB A side Detail 3 3V_MAIN C9005 PIN1 Q9002 ...
Страница 26: ...26 Troubleshooting BMX Probing Points I2C Line Check BMX A Side CL8412 I2C_S_CLOCK CL8411 I2C_S_DATA ...
Страница 28: ...28 Troubleshooting BMX B Side JL9008 3 2 5 LED BLINKING 6x Backlight Error ...
Страница 43: ...43 Troubleshooting BMX Probing Points BMX B Side JL8401 PANEL_VCC ...
Страница 44: ...44 Troubleshooting F8401 12V_REG BMX Probing Points BMX A Side ...
Страница 45: ...45 Troubleshooting IC9013 Pin 4 BL_ON BMX Probing Points BMX A Side ...
Страница 46: ...3 4 1 Video Analog Signal Path 46 ...
Страница 49: ...49 C6302 R6069 R6303 BMX BOARD A Side Troubleshooting ...
Страница 52: ...52 BMX BOARD A Side C6302 R6069 R6303 Troubleshooting ...
Страница 54: ...54 BMX BOARD A Side R6016 R6015 C6004 R6001 C6005 R6002 Troubleshooting ...
Страница 55: ...55 R6321 R6322 BMX BOARD A Side Troubleshooting ...
Страница 57: ...CN5401 R5425 R5427 R5424 RB5405 RB5406 RB5407 RB5408 57 BMX A side HDMI1 Troubleshooting ...
Страница 59: ...BMX A side HDMI2 CN5601 IC1000 R5606 R5616 R5615 RB5603 RB5604 RB5609 RB5610 59 Troubleshooting ...
Страница 61: ...CN5601 IC1000 R5611 R5602 R5603 RB5605 RB5606 RB5600 RB5601 61 BMX A side HDMI3 Troubleshooting ...
Страница 63: ...CN5602 IC1000 R5614 R5608 R5607 RB5607 RB5608 RB5612 RB5613 63 BMX A side HDMI4 Troubleshooting ...
Страница 65: ...R5445 R5444 R5443 R5424 65 BMX A side Troubleshooting ...
Страница 67: ...67 Troubleshooting Voltage check Power Key Muffin Pin R1089 R1085 Voltage check Key AD muffin Pin BMX A SIDE ...
Страница 69: ...R1124 R1062 69 BMX A SIDE Voltage check IR Muffin Pin ...
Страница 71: ...R1061 71 BMX A SIDE Voltage check Opt_Sensor Muffin Pin ...
Страница 94: ...94 5 3 Connector Diagram Diagrams 5 3 1 43 ...
Страница 95: ...95 5 3 Connector Diagram Diagrams 5 3 2 50 ...
Страница 96: ...96 5 3 Connector Diagram Diagrams 5 3 3 55 ...
Страница 97: ...97 English 2015 07 Sony EMCS Malaysia Sdn Bhd RDCM 9 888 172 04 ...