JVC UX-L30, Service Manual

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UX-L40/UX-L30
Flow of functional operation until TOC read (CD)
Slider turns REST
SW ON.
Automatic tuning
of TE offset
Laser ON
Detection of disc
Automatic measurement of
Focus A-curve amplitude
Automatic tuning of
Foucus offset
Disc is rotated
Focus servo ON
(Tracking servo ON)
Automatic tuning of
Tracking error balance
Automatic measurement of
Tracking error amplitude
Automatic tuning of
Focus error balance
Disc to be
braked to stop
Tracking
servo
on statas
Tracking
servo
off statas
Disc statas
to rotate
TOC reading
finishes
Automatic measurement
of TE amplitude and
automatic tuning of
TE balance
500mv/div
2ms/div
Fig.1
Approx.3sec
pin 20 of
IC601(TE)
Approx
1.8V
VREF
Tracking error waveform at TOC reading
Power ON
Power Key
Confirm that the Focus error
S-cuve siganl at the pin23 of
IC601 is approx.2Vp-p
Confirm that the siganl from
pin22 IC603 is 0V as a
accelerated pulse during
approx.400ms.
Confirm the waveform of
the Tracking error signal
at the pin20 of IC601
(See fig-1)
Automatic tuning of
Focus error gain
Automatic tuning of
Tracking error gain
TOC reading
Play a disc
Confirm the eys-pattern
at the lead of TP1
Check that the voltage at the pin4
of CN601 is 0V (a moment)?
Check Point
Check that the voltage at the
pin2 of IC601 is 0V?