Toshiba SD-1200 Service Manual page 56

Disc kind misjudgement
(Initial setting is NG.)
Are FE and SBAD
N
signals for each disc normal?
Check peripheral
circuit of IC601.
Check IC502.
Lens cleaning.
Replace pickup head.
Fig. 1-3-4
DVD single (single-layer) disc
detection waveform
Pin150 (TP405) of IC401
Pin152 (TP503) of IC401
V : 500 mV/div
H : 2 ms/div
Fig. 1-3-6
2-2
Y
DVD dual (dual-layer) disc
FE signal
1.65V
SBAD signal
lop 50 mA
Check pins 14, 15
and 16 of IC502
serial bus.
Check peripheral
circuits of IC502,
Q501.
detection waveform
V : 500 mV/div
H : 2 ms/div
Fig. 1-3-7
3
Check laser current.
Check laser current.
50 mA lop 90 mA
lop = Voltage between
(E534 and E536)/10Ω
Y
Check peripheral circuits
of IC502, Q501.
Fig. 1-3-5
detection waveform
Fig. 1-3-8
lop 90 mA
Check wiring for
pickup head.
Replace pickup
mechanism.
CD disc
V : 500 mV/div
H : 2 ms/div