Electrical Adjustments; Outline; Precautions For Adjustment; Adjustment Sequence - Sony MZ-G755 Service Manual

MZ-G755

5-1. Outline

• In this set, automatic adjustment of CD and MO can be per-
formed by entering the test mode (see page 12).
However, before starting automatic adjustment, the memory
clear, power supply adjustment, and laser power check must be
performed in the manual mode.
• A key having no particular description in the text, indicates a
set key.
• For the LCD display, the LCD display on the set is shown.

5-2. Precautions for Adjustment

1. Adjustment must be done in the test mode only.
After adjusting, release the test mode.
2. Use the following tools and measuring instruments.
• CD disc TDYS-1 (Check MD disc)
• MO disk (SONY MD disc available on the market)
• Digital voltmeter
• Laser power meter LPM-8001
• Thermometer (using the Temperature Correction)
3. Unless specified otherwise, supply DC 3V from the DC IN
3V jack (J601).
4. Switch position
HOLD switch ............................................... OFF

5-3. Adjustment Sequence

1. NV Reset (Memory clear)
2. Power Supply Manual Adjustment
3. Temperature Correction (item number: 014)
4. Laser Power Check
5. Electrical Offset Adjustment
Caution: This adjustment must be made with
no disc loaded.
6. CD Overall Adjustment
7. MO Overall Adjustment

5-4. NV Reset

Caution: In this set, certain adjustment values are set in the manual
mode at the factory.
NV reset will cause data to be cleared.
So, the adjustment values should be set again just after
NV reset is made.
18
SECTION 5

ELECTRICAL ADJUSTMENTS

(Part No. : 4-963-646-01)
(Part No. : J-2501-046-A)
Manual Mode
Overall Mode
Manual Mode
Overall Mode
Manual Mode
• Setting method of NV reset
1. Select the manual mode of the test mode, and set item number
021NV Reset (see page 13).
This set LCD display
ResNV CC
2. Press the key.
X
This set LCD display
Res OK?
3. Press the X key once more.
This set LCD display
Res
Reset!
4. Press the key to quit the manual mode, and activate the
x
test mode (display check mode).
• Change of adjusted values
1. Item numbers in which the adjusted values are to be modified
Item number 832
Item number 862
Item number 871
Item number 872
2. Adjusted values modifying procedure
1) Select the manual mode of the test mode, and set item number
832 (see page 13).
This set LCD display
Pw-T W
: Adjusted value
[VOL +]
2) Adjust with the
key (adjusted value down) so that the adjusted value becomes
E4.
0 21
0 21
0 21
NV reset (after several seconds)
0 21
8 32
[VOL --]
key (adjusted value up) or