Panasonic TC - 29 v30r color TV audio distortion, and with a crackle, small volume and fault maintenance methods |
| Time£º2014-05-26 10:16:37 Source£ºNetwork Author£ºUnknown Clicks£º1392 |
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qBjservice manual download site
qBjservice manual download site
Measuring Q2429 b very nearly 1.5 VP - P jamming signal, measured again left end R2424 interference signal amplitude up to 8 VP - P. R2424 left by the E18 feet, even to the output of the switch power supply, almost all of the dc voltage output switching power supply without rectifier filter circuit, when the normal due to the existence of the dc voltage output filter capacitor, so there should be no interference signals. Switching power supply output filter capacitor failure? Only about 5.5 V dc voltage measurement E18 end also. Remove the vice power filter capacitor C885 (10 mu 35 v/F) measuring has no capacity. After the replacement troubleshooting. At this point it voltage rise to normal (measured 8.3 V). qBjservice manual download site
qBjservice manual download site
The root of the failure of the vice switching circuit output filter circuit, and fault phenomena appeared in the audio. As deputy power IC803) AN78M05LB) after the output voltage of voltage stability and C889 filtering, so although C885 has failed, but did not affect IC803 5 v output voltage, thus the normal work of the CPU is not affected.qBjservice manual download site
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