Sharp MD-DR470H, Руководство по обслуживанию

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MD-DR470H/MD-DR480H
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• Recording/playback operation
Yes
No
Does level of pin 2 of IC401 change depending on record and
playback ?
Is RF pattern output from IC201 pins 36 and 37 ?
Yes
No
Check for soldering failure of IC201 .
No
Check for soldering failure of IC401 .
Yes
No
No
Check the periphery of IC501 and the waveform of the pins
97 and 100 to 102 of IC201.
No
When pressing the /- button in the recording mode and
check if a pulse waveform appears in pins 3 to 5 of IC701. If not,
even after soldering IC701, replace it.
No
Check whether the audio signal line between IC701, J701 and
J702 is defective.
Yes
Check whether input waveform is observed on the pins 6 and
7 or pins 16 and 17 of IC701.
Yes
Does the RF waveform appear at TP201A when recording/
Playback is performed ?
Check whether the pin 13 of IC501 and the pin 108 of IC201 are in
H state.
Yes
Yes
Does a digital waveform appear in pins 9 to 12 of IC501 ?
Insert a low reflection disc, and ascertain audio output by normal playback, and then set TEST REC mode.
Change MSL from 00
H
to 80
H
by the control setting of EEPROM. After completing the operation, return in to 00
H
.
Does the head move down, failing to start record even when
the continuous record mode is set after address ?
Check whether there is any damage in IC101, periphery of
laser diode.
Check for defects of IC351, IC353, IC354 and D351 in head
drive, flexible PWB.
Enter the normal recording mode.
Is audio waveform observed on the pins 1 and 19 of IC701 ?
Check voltage of pins 90 and 91 of IC201, pins 17, 18, 20, and 21
of IC601, pins 8 and 9 of CN601.
Check whether disc is record-inhibited.