Read JBL SG 2020 Service Manual online
Fails to initial read
-10-
1.3V
A
B
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
Does laser light?
Disc motor turns.
Does RF
waveform
appear?
waveform
appear?
TP 801(RF)
Does tracking
servo work?
Lower envelope
of TP801(RF)
waveform is flat.
servo work?
Lower envelope
of TP801(RF)
waveform is flat.
Does signal
appear at
TP801(TEO)?
appear at
TP801(TEO)?
Does signal appear at IC 803
Pin and Pin ?
Pin and Pin ?
Does GFS (IC802 pin
)
show as below?
Is rotation normal?
Is there no dropout of RF
signal?
signal?
Does TE2 signal
appear at pin
appear at pin
53
of IC801?
Defective IC
801, pick up
and/or open
wire.
801, pick up
and/or open
wire.
Detective pattern.
Defective IC 801
and/or IC 803
and/or IC 803
Defective pick-up
and/or connector.
and/or connector.
Defective IC 801.
Scratch in disc
initial read area.
initial read area.
Defective pick-up
adjustment focus offset.
adjustment focus offset.
26
27
25
Click on the first or last page to see other SG 2020 service manuals if exist.