Flow Of Function Operation Until Toc Read - JVC RC-EZ31A Service Manual

Flow of functional operation until TOC read
Tracking error waveform at TOC reading
pin 14 of
IC902(TE)
Approx 3sec
Approx
1.8V
VREF
Tracking
Tracking
servo
servo
off status
on
statues
Disc status
to rotate
Automatic measurement
of TE amplitude and
automatic tuning of
TE balance
Power Key
Disc to be
braked to
stop
TOC reading
finishes
500mV/div
2mS/div Fig.1
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
5
RC-EZ31
Check Point
Check that the voltage at the pin
63 of IC902 is OV (a moment)?
Check that the voltage at the
pin1 of IC902 + side is + 5V?
Confirm that the Focus error
s-cuve signal at the pin16 of
IC902 is approx.2V p-p
Confirm that the signal from
pin14 IC902 is 0V as a
accelerated pulse during
approx.400ms
Confirm the waveform of
the Tracking error signal
at the pin14 of IC902
(See fig-1)
Confirm the eys-pattern
at the lead of TP1