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VI.SPECIFIC INFORMATIONS
A. Principle integrated circuits
1. RGBTV25F99 color TV set composed of the following sections
(1) Microprocessor control: microprocessor N901 (WH2000) and memory N902
(KS24C08).
(2) Small signal processing: super monolithic integrated circuits N201 (TDA8844)
(3) Sound processing and power amplifying: integrated circuits N701 (TDA9859) and
sound power amplifying integrated circuits N601 (TDA7297)
(4) Line and field scan output integrated circuits: field output integrated circuits N301
(TDA8350Q), line output tube V403 (2SD1887YD), line output transformer T444
(BSC285314F)
(5) Video amplifying: video amplifying integrated circuits N501 (TDA6107Q)
(6) Switch power supply: switch transformer T801 (BCK10002), power integrated
circuits N801 (KA3S0680RFBYDTU), secondary power integrated circuits N804
(KA7630)
2. Main integrated circuits:
(1) WH2000
Microprocessor
(2) TDA8844
Picture IF/sound IF/video processing/line and field
scan/color decoding
(3) TDA9859
Multifunction TV stereo sound processing integrated
circuits
(4) TDA8350Q
Field output integrated circuits
(5) TDA6107Q
Video amplifying integrated circuits
(6) TDA7297
Sound power amplifying integrated circuits
(7) KA3S0680RFBYDTU
Power integrated circuits
(8) KA7630
Secondary power integrated circuits
3. Electrical circuit analysis
1. Microprocessor WH2000
Information introducing functions and testing data for maintenance is listed in Table 1.
Test information is listed beneath VHFL, if a cylindrical color card is installed then a
FLUKE 79 III meter is used.
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