Sony MZ-N420D Service Manual page 24

MZ-N420D
Laser Power Check
Note: If result of measurement of the laser power does not satisfy the
specification, either replace the OP (optical pick-up unit) or check
whether the laser circuit block is working correctly.
When the result of laser power measurement does not satisfy the
specification even though the laser circuit block is confirmed to be
working correctly, replace the OP (optical pick-up unit).
• Connection
optical pick-up
objective lens
• Checking and adjusting method
1. Select the manual mode of test mode (see page 14), and set the
laser power checking mode (item number 010).
Set LCD display
010
L a s e r
2. Press the key continuously until the optical pick-up moves
.
to the most inward track.
3. Open the cover and set the laser power meter on the objective
lens of the optical pick-up.
4. Press the key, and set the laser MO read check mode
>
(item number 011).
Set LCD display
011
# # # S * *
address
5. Check that the laser power meter reading is 0.800 ± 0.10 mW.
6. Press the > key, and set the laser CD read check mode (item
number 012).
Set LCD display
012
# # # S * *
address
7. Check that the laser power meter reading is 0.910 ± 0.11 mW.
8. Press the key, and set the laser MO (X2 speed) write
>
check mode (item number 013).
Set LCD display
013
# # # S * *
address
24
laser
power meter
adjusted value
adjusted value
adjusted value
9. Check that the laser power meter reading is 4.95 ± 0.59 mW.
10. Press the key, and set the laser MO (X4 speed) write
>
check mode (item number 014).
Set LCD display
014
# # # S * *
address
11. Check that the laser power meter reading is 5.93 ± 0.71mW.
/CANCEL key to quit the manual mode, and ac-
12. Press the x
tivate the test mode (display check mode).
Overall Adjustment Mode
• Configuration of Overall Adjustment Mode
Overall adjustment mode
(Title display)
"Assy**"
Continuing overall adjustment
key
.
> key
[VOLUME +]
[VOLUME --]
• Overall Adjustment Mode (Title Display)
Set LCD display
000
A s s y * *
: (Disc mark) At end of power supply adjustment: Outside lit
** : Left side = MO overall adjustment information
F* : MO overall adjustment completed
1* : Manual adjustment exists (overall adj. not completed)
0* : Not adjusted
Right side = CD overall adjustment information
*F : CD overall adjustment completed
*1 : Manual adjustment exists (overall adj. not completed)
*0 : Not adjusted
Note: Adjust the CD first, when performing adjustment.
adjusted value
x/CANCEL key
CD overall
adjusting
MO overall
adjusting
Electrical
key
offset
adjustment
Temperature
correction
key
and
Power supply
adjustment
auto item feed