CMT-C7NT, HCD-C7NT - Sony Audio Service Manual (repair manual). Page 41

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6. Press the  . 

“R”

  or  >

 “R”

  button so that the reading

of the laser power meter becomes the specified value, press the

ENTER/YES “R”  

button to save it.

Do not perform the emission with 8.4 mW more than 15 seconds
continuously.

7. Then,  press the  .

  “R”

    or    >

  “R”

    button to display

“LDPWR CHECK” (C13).

8. Press the  

ENTER/YES “R”  

button once to display “L0.90mW$

  ”. Check that the reading of the laser power meter matches

with the specified value as described in the following table.

9. Press the  

ENTER/YES “R”  

button once more to display

“L8.40mW$    ”. Check that the reading the laser power meter
and digital voltmeter satisfy the specified value.
Note down the digital voltmeter reading value.

Specified Value:
Laser power meter reading :

Digital voltmeter reading : Value on the optical pick-up label ±10%

10. Press the  

MENU/NO “R”

  button to display “LDPWR CHECK”

(C13) and stop the laser emission.
(The  

MENU/NO “R”

  button is effective at all times to stop the

laser emission)

11. Press the  . 

“R”

  or  >

 “R”

  button to display “Iop Write”

(C05).

12. Press the

ENTER/YES “R”

button. When the display becomes

“Ref=@@@.@” (@ is an arbitrary number), press the

ENTER/YES “R”  

button to display “Measu=@@@.@” (@ is

an arbitrary number).

13. The numbers which can be changed will blink. Input the Iop

value noted down at step 9.
To select the number : Press the  . 

“R”

  or  >

 “R”

  button.

To select the digit

:Press two buttons of  

VOL -

  and

CD 

Z  simultaneously.

14. When the  

ENTER/YES “R”  

button is pressed, “Complete!” will

be displayed momentarily. The value will be recorded in the non-
volatile memory and the display will become “Iop Write” (C05).

After step 9, each time the  

ENTER/YES “R”  

button is pressed, the

display will be switched to “L0.70mW$    ”, “L7.50mW$    ” and

“LWP 

 $    ” Nothing needs to be performed here.

Write the reference values in the nonvolatile memory to perform
“Iop compare”. As this involves rewriting the reference values, do
not perform this procedure except when adjusting the laser power
during replacement of the optical pick-up and when replacing the
IC102. Otherwise the optical pick-up check may deteriorate.

 Perform this function with the optical pick-up set at room temperature.

Procedure:
1. Press the  . 

“R”

  or  >

 “R”

  button to display “Iop NV Save”

(C06).

2. Press the

ENTER/YES “R”

button and display “Iop [stop]”.

3. After the display changes to “Iop =xxsave?”, press the

ENTER/YES “R”

button.

4. After “Complete!” is displayed momentarily, the display changes

to “Iop [8.4 mW]”.

5. After the display changes to “Iop=yysave?”, press the

ENTER/YES “R”

button.

6. When “Complete!” is displayed, it means that Iop NV saving

has been completed.

Data will be erased during MO reading if a recorded disc is
used in this adjustment.

If the traverse waveform is not clear, connect the oscilloscope
as shown in the following figure so that it can be seen more
clearly.

KMS-262A
KMS-262E

8.2 to 8.6 mW
8.5 to 8.8 mW

KMS-262A
KMS-262E

0.84 to 0.92 mW
0.90 to 0.96 mW

KMS262A

20101

B0825

Iop = 82.5 mA in this case
Iop (mA) = Digital voltmeter reading (mV)/1 (

Ω

)

(Optical pick-up label)

For details of the method for
checking this value, refer to 
“8. Recording and Displaying
the Iop Information”

KMS-262A
KMS-262E

8.1 to 8.7 mW
8.4 to 8.9 mW

UV adhesive agent

Optical pick-up 

(KMS-262A/262E)

Pink

: KMS-262A

White : KMS-262E

UV adhesive agent =

+
–

oscilloscope

(DC range)

10 pF

330 k 

Ω

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)

BD (MD) board

+
–

oscilloscope

(DC range)

V: 0.1 V/div
H: 10 ms/div

BD (MD) board

CN105 pin 

4

 (TE)

CN105 pin 

6

 (VC)