Flow Of Functional Operation - JVC RV-B550BU Service Manual

Flow of functional operation until TOC read
Power ON
Tracking error waveform at TOC reading
Approx.3sec
pin 25 of
IC601(TE)
Approx
1.8V
VREF
Tracking
servo
off statas
Disc statas
to rotate
Automatic measurement
of TE amplitude and
automatic tuning of
TE balance
Slider turns REST
Power Key
Automatic tuning
of TE offset
Detection of disc
Automatic tuning of
Automatic measurement of
Focus A-curve amplitude
Automatic measurement of
Tracking error amplitude
Tracking
Disc to be
servo
braked to stop
Automatic tuning of
on statas
TOC reading
Tracking error balance
finishes
500mv/div
2ms/div Fig.1
SW ON.
Laser ON
Foucus offset
Disc is rotated
Focus servo ON
(Tracking servo ON)
Automatic tuning of
Focus error balance
Automatic tuning of
Focus error gain
Automatic tuning of
Tracking error gain
TOC reading
Play a disc
RV-B550BU
Check Point
Check that the voltage at the pin 5
of CN602 (or pin 5 of IC901)
is 0V (a moment)?
Check that the voltage at the
pin3 of IC601 + side is + 5V?
Confirm that the Focus error
S-cuve siganl at the pin27 of
IC601 is approx.2Vp-p
Confirm that the siganl from
pin24 IC603 is 0V as a
accelerated pulse during
approx.400ms.
Confirm the waveform of
the Tracking error signal
at the pin25 of IC601 (R612)
(See fig-1)
Confirm the eys-pattern
at the lead of TP602
1-19