akira 14RBS3WN, Руководство по обслуживанию

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Model No: 14RBS3Wn
Version 1.0
2. Two-None (no picture, no sound)
The failure shows that the set does not display the picture but it has noise wave or blue background or
OSD on the screen. This means that the circuits of power supply, horizontal scanning, vertical scanning
and video amplification are normal and they are not considered in the repairing. The failures are mainly
in the small signal processing circuits.
Before checking these circuits, a kind of practical test method is introduced .It is called Signal-input
way .The detail is described as follow:
W e can use the resistance function of an analog multimeter, connect the red pole (negative in ohm
scope) on the circuit board ground, then touch softly the test point with another pole (black pole) in
ohm scope meanwhile observe the reactivity on the output device.
Note: In the TV test, we mainly observe the noise wave on the CRT and listen to the noise voice liking
as Ka....Ka from the loudspeakers.
a. No picture