Sony MDX-C800REC Operating manual

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SUPPLEMENT-1
File this supplement with the service manual.
Subject : Electrical Adjustments
SERVICE MANUAL
MDX-C800REC
US Model
Canadian Model

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TEST MODE
This set has the test mode functionality. The test mode should be
always set before performing adjustments.
<Setting the Test Mode>
1. Input the specified voltage (14.4 V) to the ACC and BATT
terminals.
2. “1:00” is displayed on the LCD display.
3. Press 4 key.
4. Press 5 key.
5. Press 1 key for more than 2 seconds.
6. All segments are lit on the LCD display entering the test mode.
<Releasing the Test Mode>
1. Press OFF key.
DISPLAYTEST
1. Once the test mode is set, each pressing of the DSPL key will
cause the LCD display to change as follows:
All segments ON
Press DSPL key.
Half segments ON (1)
Press DSPL key.
Half segments ON (2)
(The other half segments that were OFF in (1) are ON.)
Press DSPL key.
All segments OFF
Press DSPL key.
TEST MODE STRUCTURE
1. Set the test mode.
2. Insert a disc and press 5 key.
3. Each time 6 key is pressed, the mode will change as follows:
ADJUSTMENT mode “SHUF” indication off
Press 6 key.
PLAY mode “SHUF1” indication is lit.
Press 6 key.
REC mode “SHUF2” indication is lit.
Press 6 key.
Unused mode “SHUF ALL” indication is lit.
Press 6 key.
ELECTRICAL ADJUSTMENT
ADJUSTMENT mode: SHUF indication off
Key Description of test
2 Laser power adjustment mode
3 Traverse adjustment mode
4 Focus bias adjustment mode
5STOP
6 Switch the mode
ENTER CLV jitter measurement
DSPL Select the display
PLAY mode: SHUF1
Key Description of test
2 Laser power check mode
3 Focus + CLV ON
4 Tracking servo ON/OFF
5STOP
6 Switch the mode
ENTER CPLAY mode (middle/outer/inner area)
DSPL Select the display
REC mode: SHUF2
Key Description of test
2 Laser power check mode
3 Focus + CLV ON
4 Tracking servo ON/OFF
5STOP
6 Switch the mode
ENTER CREC mode (middle/outer/inner area)
DSPL Select the display
Unused mode: SHUF ALL

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NOTES FOR ADJUSTMENT
1. Perform thefollowingadjustmentsas listed whenthe opticalpick-
up and IC400, IC402 and/or IC440 in the MD SERVO board
have been replaced:
(1) Laser power adjustment
(2) Traverse adjustment
(3) Focus bias adjustment
(4) CD error rate check
(5) MO error rate check
2. Set the test mode to perform these adjustments. Release the test
mode after the adjustments are completed.
3. Perform the adjustments in the order that they are listed.
4. Use the following jigs and measuring equipment:
• Test disc (special disc for playback) TDYS-1
(Part No.: 4-963-646-01)
• Laser power meter LPM-8001
(Part No.: J-2501-046-A)
• Oscilloscope (Measure after the probe is calibrated.)
• Digital voltmeter
5. When observing multiple signals with an oscilloscope or other
equipment, take care to prevent connection between VC and
ground in the oscilloscope. (Otherwise, VC and ground are
shorted.)
PREPARING A CONTINUOUSLY RECORDED DISC
• This disc is used for focus bias adjustment and error rate check.
This disc is prepared as follows:
1. Set the test mode. (See page 2.)
2. Insert a commercial disc (blank) and press 5 key.
3. Press 6 key twice to set the REC mode.
(Verify that the “SHUF2” indication is lit on the LCD display.)
4. Verify that no number is displayed at the disc No. indicator.
If any number is displayed, repeatedly press DSPL key until the
number disappears (only two digits are displayed).
5. Press ENTER key three times and verify that there is no disc
number displayed (the disc is recorded from the inner area).
If “3” or “7” is displayed, press ENTER key again to clear the
indicator. LCD display
6. Record the data until the disc number indicator shows “9” and
then press 5 key to stop recording.
7. Press Zkey and take out the disc.
The continuously recorded disc for focus bias adjustment and error
rate check is now prepared.
Note:
Take care to prevent vibrations during continuous recording.
SHUF 2
Disc No. indicator REC mode

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KMS-263A
27X93
B0825
(Optical pick-up label)
In this case, Iop = 82.5 mA
Iop (mA) = Reading on the digital voltmeter (mV)/1 (Ω
)
For the measurement points, see page 7.
LASER POWER ADJUSTMENT
Connection:
Procedure:
<Setting the write power reference value>
1. Connect a digital voltmeter between TP (I+3V) and TP (IOP).
2. Set the test mode. (See page 2.)
3. Insert a laser power meter into the disc insertion port and press 5
key.
4. Press 2 key. LCD display
+
–
optical pick-up
objective lens
laser power
meter
digital voltmete
r
MD servo board
TP (I+3V)
TP (IOP)
5. Use DISC + or DISC – key to adjust so that the reading on
the laser power meter is 6.9 to 7.1 mW.
6. Press + >Mkey for 2 seconds to save the data that has
been set in step 5.
7. Verify that the digital voltmeter reads out the specified value.
Specified value:
Reading on the digital voltmeter: Optical pick-up label indication
value ±10%
Mode No.
(LD Power Adj.)
7.0 mW power
<Setting the read power reference value>
8. Press 2 key. LCD display
9. Use DISC + or DISC – key to adjust so that the reading on
the laser power meter is 0.69 to 0.71 mW.
10. Press + >Mkey for 2 seconds to save the data that has
been set in step 9.
11. Press 2 key. LCD display
Mode No.
(LD Power Adj.)
0.7 mW power
12. Verify that the reading on the laser power meter is 6.0 to 6.4
mW.
If outside the specified value, adjust again from step 1.
13. Press 2 key. The laser power adjustment is completed.
Mode No.
(LD Power Adj.)
Main beam conversion power

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Mode No.
(Focus Bias Adj.) Represents the point B measurement
Indicates the C1 error rat
e
Mode No.
(Focus Bias Adj.) Represent the point A measurement
Indicates the C1 error rate
Mode No.
(EF-B Adj.) Represents EF adjustment
Initial set value Value after
automatic
adjustment
TRAVERSE ADJUSTMENT
Connection:
Procedure:
1. Connect an oscilloscope between TP (TE) and TP (VC).
2. Set the test mode. (See page 2.)
3. Insert the test disc TDYS-1 and press 5 key.
4. Press 3 key. LCD display
5. The traverse is automatically adjusted.Verify that the waveform
of the oscilloscope meets the specified value.
6. If outside the specified value, use DISC + or DISC – to adjust
the waveform.
Pressing of DISC + or DISC – will cause the value after
automatic adjustment to be varied.
7. Press + >Mkey for 2 seconds to save the data set in steps
5 and 6.
After saving the data, verify that the initial set value is equal to
the value after automatic adjustment.
8. Press 3 key. The traverse adjustment is completed.
+
–
oscilloscope
V: 0.5 V/div H: 10 ms/di
v
Input: DC mode
MD servo board
TP (TE)
TP (VC)
A
B
VC
(Traverse waveform)
Specification: A = B
FOCUS BIAS ADJUSTMENT
Procedure:
1. Set the test mode. (See page 2.)
2. Insert the continuously recorded disc (see page 3.) and press 5
key.
3. Press 4 key and check the error rate in the current focus bias
setting. LCD display
<Setting the focus bias point A>
4. Verify that the first digit of the C1 error rate are “0”. Then,
press 4 key. LCD display
5. Press DISC + key until the C1 error rate value reaches “1.00”
(Note 1).
6. Press + >Mkey for 2 seconds to save the data set in step
5.
<Setting the focus bias point B>
7. Press 4 key. LCD display
8. Press DISC – key until the C1 error rate value reaches “1.00”
(Note 1).
9. Press + >Mkey for 2 seconds to save the data set in step
8.
10. Press 4 key. LCD display
Mode No.
(Focus Bias Adj.) Represents the initial measurement Indicates the C1 error rate
Mode No.
(Focus Bias Adj.) Represents the calculated
point C measurement
Indicates the C1 error rat
e

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11. Verify that the calculated point C error rate is “0.30” or less.
If more than “0.30”, adjust again from step 1.
12. Press 4 key. The focus bias adjustment is completed.
Note 1) Since the C1 error rate varies, the average should be read to
perform this adjustment.
Note2) Therelationship betweenC1 errorrate andfocus biasamount
is shown in the figure below.
Find out the points A and B in the above adjustment. The
total focus point C is automatically calculated from the
points A and B.
CD ERROR RATE CHECK
Procedure:
1. Set the test mode. (See page 2.)
2. Insert the test disc TDYS-1 and press 5 key.
3. Press 6 key to set the PLAY mode.
(Verify that the “SHUF1” indication is lit on the display.)
4. Verify that no number is displayed at the disc No. indicator.
If any number is displayed, repeatedly press DSPL key until
the number disappears (only two digits are displayed).
5. Press ENTER key and verify that the disc No. indicator shows
“3”.
If “7” is shown or there is no display, repeatedly press ENTER
key until “3” is displayed.
LCD display
6. Verify that the C1 error rate is “0.30” or less.
7. Press 5 key. The CD error rate check is completed.
MO ERROR RATE CHECK
Procedure:
1. Set the test mode. (See page 2.)
2. Insert the continuously recorded disc (see page 3.) and press 5
key.
3. Press 6 key to set the PLAY mode.
(Verify that the “SHUF1” indication is lit on the display.)
4. Verify that no number is displayed at the disc No. indicator.
If any number is displayed, repeatedly press DSPL key until
the number disappears (only two digits are displayed).
5. Press ENTER key and verify that the disc No. indicator shows
“3”.
If “7” is shown or there is no display, repeatedly press ENTER
key until “3” is displayed.
LCD display
6. Verify that the C1 error rate is “0.30” or less.
7. Press 5 key. The MO error rate check is completed.
100
BC A
C1 error rate
Focus bias amount
(F. BIAS)
SHUF 1
Disc No. indicator C1 error ratePLAY mode
SHUF 1
Disc No. indicator C1 error ratePLAY mode

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I+3V
IOP
VC TE
Measurement points:
—MD SERVO BOARD (SIDE A) —

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MDX-C800REC
Sony Corporation
Audio Entertainment Group
9-870-144-82 2000F0411-1
Printed in Japan ©2000. 6
Published by ME General Engineering Dept.