(1) measuring the decoding integrated block IC601 47 feet (AN5192K - A) if the voltage is + 5 v. If the test voltage of 0 v, and check whether there is any leakage on 47 feet external capacitance or breakdown, external power supply circuit devices do you have any open circuit damage. naRservice manual download site
 naRservice manual download site
(2) using oscilloscope measurement IC601 48 feet enter chrominance signal waveform is normal (normal signal amplitude is about 1 v). If no signal waveform or signal amplitude is too low, you should check whether there is any open circuit on 48 feet external signal coupling capacitance or capacity is smaller. naRservice manual download site
 naRservice manual download site
(3) measuring IC601 5 feet voltage is normal (normal) should be 5 v, if the measured voltage is too low. Voltage measurement (4) feet again whether normal (normal is about 3.3 V), (4) the voltage is lower than 2.8 V, feet of decolorization circuit has work; Measured again 7 feet or 4.43 MHz color subcarrier signal waveform, without external should check 7 feet crystals and capacitance is metamorphic damage; If 7 feet signal is normal, check IC601 have an external device (4), 6 feet without metamorphic damage; If the voltage is normal, (4) feet check whether there is any leakage on 5 feet external filter capacitance or breakdown; If the voltage of 0 v, 5 feet confirm 5 foot external capacitance in good condition under the premise of check IC1101 (MN152811T6N) performance is bad. naRservice manual download site
 naRservice manual download site
(4) IC601 60, 61 feet output color difference signal, without IC601 test should be changed. naRservice manual download site
 naRservice manual download site
IC602 (5) test (TDA4665) 11, 12 feet have normal color difference signal waveform signal amplitude (normal both feet were 1.2 V, 1.5 V), if the two pins or no signal waveform signal amplitude is too low. Should check IC602 mainly related devices have metamorphic damage and its peripheral circuit. naRservice manual download site
 naRservice manual download site
(6) if IC602 signal waveform is normal, 11, 12 feet under the condition that normal external signal coupling capacitance rhyme, IC601 should be replaced.

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