This machine is plugged in, when the standby, the red light is lit, press the "POWER" button, the red light is put out, the green light is lit. Since then, for various operations and play sometimes, failure, various function keys and are sometimes unable to play it. In normal can play in the process of CD, sometimes figure, and suddenly disappeared, all function failure. The fault appears irregular, sometimes was turned on, sometimes play a night also have no problem. snZservice manual download site
 snZservice manual download site
The machine circuit structure is relatively complex, have some differences with VCD, SVCD, CVD dv, adopted many new circuit. To avoid detour to make the repair, first to analyze to the standby red and green leds VD6506 light process indicates the bright leds VD6505 process, and then combining with fault phenomenon to narrow the possible range. snZservice manual download site
 snZservice manual download site
The first analysis of standby red leds VD606 on process. snZservice manual download site
 snZservice manual download site
The red indicator light emitting diode VD6506 light voltage is provided by the switch power supply circuit, first to analyze the working process of the switch power supply. snZservice manual download site
 snZservice manual download site
Switch power input circuit is mainly composed of Ll001, L1002, Cl001 - C1004, ZNR, VD1001, Cl011 components (see below left half switch power supply circuit). Which is suitable for bidirectional diode ZNR overvoltage protection device to prevent damage of high power grid voltage within the machine components. Ll001 and Cl001, L1002 and C1004 constitute the two groups of different parameters of common mode filter, to get broadband inhibition effect, used to filter out the interference signal of the power grid voltage and prevention of switch power supply pulse harmonic pollution into the grid. Common mode filter has the characteristics of the power supply symmetric interference filter. This is mainly due to the filter inductance Ll001 or L1002 is in phase two coil winding, flowed over its current in the opposite direction, so that it can make the interference signal in the inductive magnetic field formed in the core offset each other, so as to achieve the goal of the common mode rejection. Two additional, Ll001 and L1002 also C1002, C1003 capacitance and inductance coil winding constitute two inverted "L" type LC filter, used to suppress the differential-mode interference signal.

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