Rotel RDV-985, Техническое руководство

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50msec
Approx.
500mV
GND
2.5V
(3) Traverse movement NG
* For automatic adjustment, traverse movement occurs only when the position is changed to retry
judging the disc type after the 1st judgment resulted in an error. Therefore, traverse movement
rarely occurs because, in most cases, disc judgment at the current position (1st time judgment)
is executed successfully. (Of course, NG rarely occurs in this step.)
Note: 1st time judgment of disc type resulted in NG. --- The re-judgment of disc type may not be
successful. Therefore, after removing the cause of traverse movement, re-execute automatic
adjustment and confirm that no problem exists.
* Check point
a)During stop
Whether 50% duty pulse is output to R273
Whether between R274 and C271 is at approx. 2.5VDC
Offset voltage between CN101 "34" and "35" (scores mV if exists)
b)When tray is opened or closed
Check by oscilloscope whether a rectangular wave signal is output from CN101 "34" or "35".
If checking a) or b) resulted in NG, IC201 maybe defective.
(4) Focus ON NG
* Is FE output ? --- Pattern, IC101
* Is FCDRV signal sent ? (R286) --- Pattern, IC301
* Is driving voltage sent ?
CN101 "20", "21" --- If NG, pattern, driver, mechanical unit (with the power turned off, measure the
resistance between CN101 "20" and "21").
* Does CN101 "7"(SRF1) become "H" and is the focus drawing in done?
--- Mechanical unit (laser power too low), IC101(defective gain)
--- Moreover, It is thought that abnormality is found in the disk.
* Mechanical unit is defective.
(5) Tracking ON NG
* When the tracking loop cannot be drawn in, IC201 "39" (/TRON) does not become "L".
* Mechanical unit is defective.
Because the under
mentioned adjustment value is abnormal, it is not possible to draw in normally.
* Periphery of driver (IC271)
Constant or IC it self is def
ective.
(When passing without becoming abnor mal while adjusting the following.)
* Servo IC (IC201)
When improper
ly adjusted due to defective IC.
[F ocus position rough adjustment]
[Phase diff erence cancellation rough adjustment]
[T racking balance adjustment]
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