Sony PMC-MD55 Service Manual page 137

CD SECTION
Set the CD test mode when performing confirmations.
After completing the confirmation, release the CD test mode.
In the CD test mode, the set works as following sequence.
CD test mode sequence:
1. Enter the CD test mode
(STOP mode 1)
Press the s (CD)
button.
2. STOP mode 2
[ , CD]
Press the
7
button.
3. FOCUS mode
[ , CD]
Press the
7
button.
4. ALL SERVO
ON mode 2
[ , CD]
Press the
7
button.
5. TRACKING
GAIN UP mode 1
[ , CD]
Press the
7
button.
6. TRACKING
GAIN UP mode 2
[ , CD]
Press the
7
button.
7. ALL SERVO
ON mode1
[ , CD]
Press the 7
button.
Note1: ALL SERVO ON mode 1 and TRACKING GAIN UP mode 1:
LPC ON (Lights up "ALL" indication)
ALL SERVO ON mode 2 and TRACKING GAIN UP mode 2:
LPC OFF (Does not lights up "ALL" indication)
*) LPC: Laser power control
Note2: TRACKING GAIN UP mode 1,2 is not used in servicing.
1. Entering the CD Test Mode
[POWER]
1. Press the button to turn the power ON.
[CD OPEN/CLOSE ]
2. Press the
and put a disc.
[CD OPEN/CLOSE ]
3. Press the
[POWER]
4. Press the button to standby state.
[BASS/TREBLE]
5. While pressing the both
[ , CD]
press the button
7
(CD).
[BASS/TREBLE]
6. Release the both
7. After display "CD" for a few seconds, enter the CD test mode
(STOP mode 1), and display as below.
Press the s (CD)
button.
Press the s (CD)
button.
Press the s (CD)
button.
Press the s (CD)
button.
Press the s (CD)
button.
Z button to open the disc lid,
button to close the disc lid.
Z
[EDIT]
and buttons,
[ ] [ , CD]
t s (CD) t t
7
[EDIT]
and buttons.
88
2. STOP Mode 2
[ ]
1. Press the s
display as below.
88
[
2. Press the
>
up to position of the track where signal is recorded.
3. FOCUS Mode (Traverse Confirmation)
[ ]
1. Press the 7
as below. (Focus servo ON. CLV-S, tacking and sled servo OFF)
11
2. Connect an oscilloscope to TP (TEO) and TP (VC) on the
MAIN board.
Connection:
MAIN board
TP (TEO)
TP (VC)
3. Confirm that the traverse level of waveform satisfy specified
value as follows.
Traverse Waveform
VC
Specified Value:
traverse level: 160 to 380 mVp-p
Connecting Location: MAIN board (See page 29)
[ ]
s
– 28 –
Display
XX XX XXX
(CD) button to enter the STOP mode 2, and
Display
07 00 3A0
] [ ]
and button to move the optical pick-
.
button to enter the FOCUS mode and display
Display
07 00 3A0
oscilloscope
(DC range)
+
–
A
traverse level:
160 to 380 mVp-p
B
A = B