Sony PMC-MD55 - Md Boombox, Service Manual

Page: 28 / 220

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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:
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
1. Press the
[POWER]
button to turn the power ON.
2. Press the
[CD OPEN/CLOSE ]
button to open the disc lid,
and put a disc.
3. Press the
[CD OPEN/CLOSE ]
button to close the disc lid.
4. Press the
[POWER]
button to standby state.
5. While pressing the both
[BASS/TREBLE]
and
[EDIT]
buttons,
press the button
[ , CD]
n
[ ]
(CD)
n
[ , CD]
n
[ ]
(CD).
6. Release the both
[BASS/TREBLE]
and
[EDIT]
buttons.
7. After display “CD” for a few seconds, enter the CD test mode
(STOP mode 1), and display as below.
1. Enter the CD test mode
(STOP mode 1)
Press the
π
(CD)
button.
2. STOP mode 2
3. FOCUS mode
4. ALL SERVO
ON mode 2
5. TRACKING
GAIN UP mode 1
6. TRACKING
GAIN UP mode 2
7. ALL SERVO
ON mode1
Press the
π
(CD)
button.
Press the
[ , CD]
button.
fl
Press the
[ , CD]
button.
fl
Press the
[ , CD]
button.
fl
Press the
[ , CD]
button.
fl
Press the
[ , CD]
button.
fl
Press the
[ , CD]
button.
fl
Press the
π
(CD)
button.
Press the
π
(CD)
button.
Press the
π
(CD)
button.
Press the
π
(CD)
button.
fl π fl
π
88 XX XX XXX
88 07 00 3A0
[ ]
[ ] [ ]
Display
2. STOP Mode 2
1. Press the
π
(CD) button to enter the STOP mode 2, and
display as below.
Display
2. Press the
+
and
=
button to move the optical pick-
up to position of the track where signal is recorded.
3. FOCUS Mode (Traverse Confirmation)
1. Press the
fl
button to enter the FOCUS mode and display
as below. (Focus servo ON. CLV-S, tacking and sled servo
OFF)
Display
2. Connect an oscilloscope to TP (TEO) and TP (VC) on the
MAIN board.
Connection:
3. Confirm that the traverse level of waveform satisfy specified
value as follows.
Traverse Waveform
Specified Value:
traverse level: 160 to 380 mVp-p
Connecting Location: MAIN board (See page 29)
11 07 00 3A0
+
–
MAIN board
TP (TEO)
TP (VC)
oscilloscope
(DC range)
A
traverse level:
160 to 380 mVp-p
B
VC
A = B
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