Haier DX-RCRT20-09, Руководство по обслуживанию

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5. Analysis of horizontal sync and horizontal scan output circuits
As the horizontal oscillation circuit is installed inside IC201 (R2J10165GF), .
Some brightness signals including compound sync signals are transmitted to the
internal sync segregation circuits, where horizontal sync and vertical sync pulses are
segregated. Horizontal pumping signals are transmitted from (15) of IC201 to
horizontal promotion transistor Q401 (2SC2383), and then drive the H-DRIVE
transformer. After being amplified through it switches power transistor Q402 (2SC5885)
to control the horizontal scan of the electronic-beam.C418 is a horizontal S correction
capacitor and L401 is for horizontal linear inductor. T401 is a horizontal output
transformer. The horizontal return pulse output from (ABL) of T401 is transmitted to pin
(49) of IC201 who controls ABL circuits. ABL avoid high-voltage over rated value that
will cause X-ray and affect your health.
6. Analysis of video amplifying circuits
The video amplifying circuits are comprised of V501, V502, V503 and peripheral
components. R, G and B signals output from IC201 (51), (52) and (53), 3 video power
transistor are available for amplifying the input R, G, B. White balance adjustment is
completed through IC602 under control of an I
2
C serial bus control system.
7. Maintenance Service and Trouble shooting
A. Principle integrated circuits
A1. 21 INCH color TV set composed of the following sections
(1) Small signal processing: super monolithic integrated circuits IC201
(R2J10165GF). and memory IC602 (AT24C16).
(2) Sound power amplifying: integrated circuits IC701 (TFA9800J).
(3) Horizontal and Vertical scan output circuits: Vertical output integrated circuits
IC401 (LA9302), Horizontal output transistor Q402 (2SC5885), Horizontal
flying back transformer T401 (JF0501-32806).
(4)
Switch power supply: switch transformer T901 (BCK-80-F404LE), power IC
IC901 (TEA1506/N1), MOSFET (7N60B/IRFBC40).
A2. Main integrated circuits:
(1) R2J10165GF Microprocessor
Picture IF/sound IF/video processing/H and V
Scan/color decoding
(2) LA9302 Vertical output integrated circuits
(3) TFA9800J Sound power amplifying integrated circuits