PIONEER MJ-L77
Manual de Servicio

MJ-L77

7 MD mech adjustment items
Note: The operation buttons mentioned in the following explanations are those for the MJ-L77 or the remote control equipped with the product. When using the service remote control, refer to the key comparison table on the previous page.

1 Temperature Check (Please perform this check soon after the power has been switched on.)
Note: When IC101 (RF-AMP), IC104 (mechanical controller) or IC110 (EEPROM) has been exchanged or when a correction changing VD+3 has been made, be sure to correctly perform all steps up to step 6.
Step No. 1 2 3 When 4 Operation Keys and Operation Method Turn on the power. Then, short the MECHA TEST jumpers (W4076 and W4098). Press the MD REC key. When is 80 or more at this time, the adjustment is OK (step 4 and following can be omitted). is 80 (not passed) Measure the ambient temperature T (°C) andcheck hat the measuring value ( ) is within the standard in regard to the microcomputer set value ( ). Note: When the indication of the measuring value ( ) is not stable, and the ambient temperature T (°C) is 25 °C or less, set to the lower value. When the ambient temperature is over 25 °C, set to the higher value. TEMP 80 FL Display EJECT TEMP Test mode The microcomputer starts measuring. End 80 is the default value (unadjusted).
TEMP µ-com Measuring value Room Temperature [ T (°C) ] 11.6 to 16.9 17.0 to 22.3 22.4 to 27.6 27.7 to 33.0 33.1 to 38.4 ( hex= � +1 to +3 0 to +2 �1 to +1 0 to �2 �1 to �3 ) 79 When the 7A microcomputer 7B value is 7C 7D µ-com Set value

Status

Remarks

: Measuring value : Set value

�

+

5 6

Change with the ¢ key (UP) and the 4 key (DOWN). Power OFF

TEMP 7B 7B No Disc Writing to EEPROM is made and return is made automatically from test mode to normal mode.

2 Laser Power Check
CAUTION
� Never look directly at the objective lens. Rec power (rpw) is than ten times greater than Playback power (ppw) is released. � Never turn the pickup volume and be careful of touch it. Laser power of pickup has been adjusted in the factory shipping.
Step No. 1 2 3 4 Operation Keys and Operation Method Turn on the power. Then, short the MECHA TEST jumpers (W4076 and W4098). Press the SET key. Measure the laser power with an optical power meter. At this time, check that the measuring value (PLAY power) meets the standard value of the table on the right. Note: When the standard value on the right is applied, the numerical value immediately after entry into MD mech adjustment mode shall be taken as the standard. FL Display EJECT ppw ppw ppw Test mode PLAY power output status Status Remarks Laser Wavelength: 780 nm

TEMP µ-com Measuring value
( hex = � +02 to +04 �01 to +01 �02 to �04 )

May be omitted.

µ-com Set value
Standard Value (mW) 0.69±0.12 0.67±0.1 0.63±0.1

5

Press the SET key.

rpw

REC power output status

36