Sharp XL-DK225 - Focus-RF System Check

XL-DK225
7 – 2
Although a CD is inserted and the cover is closed,
"NO DISC" is displayed.
(1) Focus-RF system check.
Press the Tray1 CD Eject Button without inserting a disc, and try
starting the playback operation.
Figure 1
IC1
IC1
1
22
23
2
FDO
TDO
1. Does the pickup move to the PICKUP-IN Switch (NSW1)
position?
No Sled motor (NM2).
Yes
2. Does the focus (lens) move up and down?
(Waveform drawing Figure 1)
No Check the focus peripheral circuit.
Yes
3. Is the laser lit? No Check the laser diode driver Q1 peripheral circuit.
Yes
4. Is the turntable rotating? No Spindle motor (NM1).
When a disc is loaded, start playback operation.
1. Is focus servo activated?
(Waveform drawing Figure 2)
No Pins 5~9, 11, 18 19 and 22 on IC1
Check the laser diode driver Q1 peripheral circuit.
Yes
2. Is the RF waveform normal?
(Waveform drawing Figure 3)
No If the level is not normal.
Figure 2
IC1
IC1
22
16
3
1
FDO
TE
Figure 3
IC1
2
RFOUT
4