Flow Of Functional Operation Until Toc Read - JVC UX-G6 Service Manual

UX-G6/FS-G6

Flow of functional operation until TOC read

Power ON
Tracking error waveform at TOC reading
Approx.3sec
pin 25 of
IC462(TE)
Approx
1.8V
VREF
Tracking
servo
off states
Disc states
to rotate
Automatic measurement
of TE amplitude and
automatic tuning of
TE balance
2-18
Play Key
Automatic measurement of
Focus S-curve amplitude
Focus servo ON
(Tracking servo ON)
Automatic measurement of
Tracking error amplitude
Tracking
Disc to be
servo
braked to stop
on states Automatic tuning of
TOC reading
finishes
Tracking error balance
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
Disc is rotated
Automatic tuning of
Focus error balance
Automatic tuning of
Focus error gain
Automatic tuning of
Tracking error gain
TOC reading
Play a disc
Check Point
Confirm that the voltage at the pin5
of CN440 is "H"\"L"\"H".
Check that the voltage at the
pin40 of IC461 is + 5V?
Confirm that the Focus error
S-cuve signal at the pin28 of
IC462 is approx.2Vp-p
Confirm that the signal from
pin24 IC461 is 0V as a
accelerated pulse during
approx.400ms.
Confirm the waveform of
the Tracking error signal.
at the pin 25 of IC462 (R4628)
(See fig-1)
Confirm the eys-pattern
at the lead of P4601