Sharp MD-MS200W Service Manual page 41

• Normal playback
When the address up to the sector address has been proved to be normal in the test mode.
Is initialization performed normally in case of high reflection
disc normal playback?
Is the read-in switch turned on when the optical pickup is
moved to the innermost periphery in NORMAL mode?
(Is the pin 48 of IC401 on L level?)
Is an attempt tp read repeatebly the TOC section of low
reflection disc made?
Position check in INNER mode
• Audio playback circuit
Although the playback time display is acting, no sound is given during playback in the normal mode.
Is audio waveform output from IC501 pins 26 and 27?
Is audio waveform output from IC703 pins 18 and 19.
Is audio waveform output from J703 pins 4 and 5.
Check headphones jack,and periphery of headphone.
• The disc motor fails to rotate.
Is waveform observed on the pins 58 and 59 of IC201 in
focus gain rough adjustment step?Is audio waveform Is
waveform observed on the pins 21 of IC601?
Do the pins 16 and 21 of IC901 waveform observe?
Replace the disc motor.
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
MD-MS200W/MD-MS200/MD-MS200H
Does the playback time display act?
Yes
No
Check IC201 and IC202 connection line.
Check the lead-in switch SW901, solder joint of mechanism
No
PWB, and the pin 8 of CNS601.
Check whether the disc is new one.
No
Check IC201 pins 76 to 78, pin 80 and IC501 pins 11, 12, 13, 15.
No
Check the pins 5 and 6 of IC703.
No
Check whether there is defective solder joint of audio signal line
No
between IC703 and J703.
Check the periphery of IC201.
No
Replace IC601.
No
Check solder joints of L607, IC201, IC901, CNS601, and flexible
No
PWB.
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