JVC PC-X250 - TOC Read

Flow of functional operation until TOC read
Check Point
Check that the voltage at the pin
16 of IC903 is OV (a moument)?
Check that the voltage at the
pin64 of IC901 + side is + 5V?
Confirm that the Focus error
s-cuve signal at the pin16 of
IC901 is approx.2V p-p
Tracking error waveform at TOC reading
Confirm that the signal from
pin27 IC901 is 0V as a
accelerated pulse during
approx.400ms
Confirm the waveform of
the Tracking error signal
at the pin15 of IC901 (R975)
(See fig-1)
Confirm the eys-pattern
at the lead of TP1
Power ON Power Key
Slider turns REST
SW ON.
Automatic tuning
of TE offset
Laser ON
Detection of disc
Automatic tuning of
Focus offset
Automatic measurement of
Focus A-curve amplitude
Disc is rotated
Focus servo ON
(Tracking servo ON)
Automatic measurement of
Tracking error amplitude
Automatic tuning of
Tracking error balance
Automatic tuning of
Focus error balance
Automatic tuning of
Focus error gain
Automatic tuning of
Tracking error gain
TOC reading
Play a disc
Approx 3sec
pin 15 of
IC901(TO)
Tracking
servo
off status
Tracking
servo
on status
Disc to be
braked to
stop
TOC reading
finishes
Disc status
to rotate
Automatic measurement
of TO amplitude and
automatic tuning of
TO balance
500mV/div, 2mS/div Fig.1
VREF
Approx
1.8V
PC-X250
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