D-EQ550
7
7
Focus bias Check
Condition:
• Hold the set in horizontal state.
Connection:
Procedure:
1. Connect the oscilloscope to the test points TJ503(RFI) and TJ610
(VBIAS) on the MAIN board.
2. Set a disc. (YEDS-18)
3. Press the
>B
button.
4. Check the oscilloscope waveform is as shown below.
A good eye pattern means that the diamond shape (
◊
) in the
center of the waveform can be clearly distinguished.
RF Signal reference Waveform (Eye Pattern)
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy
watching.
5. Stop revolving of the disc motor by pressing the
x
button.
S801
(OPEN/CLOS
C301
C619
C802
IC603
TP814
C106
R620
TAP806
C634
TJ502
R631
TJ608
TP817
TP609
TP616
R824
0
TP503
TJ303
C306
R209
C10
TJ603
C203
TP507
TJ610
R205
TP603
TJ604
D801
TAP803
TJ405
TJ601
TJ602
TJ607
TAP805
TJ501
Q601
TJ503
TAP601
TP621
IC302
R109
C206
C610
R605
R107
D805
R617
R613
R614
R615
L601
HPLOUT
AVDD
AGND
LD
RFI
AVDD
LASER
MON1
MON2
CLK4M
FOK
RF1
SCOR
XBUSY
C2POEN
PD
VBIAS
OPSTB
RFGO
.4V
TJ610 (VBIAS)
TJ503(RFI)
oscilloscope
(AC range)
The CD section adjustments are done automatically in this set.
Precautions for Check
1. Perform check in the order given.
2. Use YEDS-18 disc (Part No.: 3-702-101-01) unless otherwise
indicated.
3. Power supply voltage requirement : DC4.5 V in DC IN jack.
(J401)
VOLUME button : Minimum
HOLD switch : OFF
– MAIN BOARD (SIDE B) –
RF level
0.45 to 0.70 Vp-p
VOLT/DIV : 100 mV (With the 10 : 1 probe in use)
TIME/DIV : 500n
s
SECTION 4
ELECTRICAL ADJUSTMENTS
w w w . x i a o y u 1 6 3 . c o m
Q Q 3 7 6 3 1 5 1 5 0
9
9
2
8
9
4
2
9
8
T E L
1 3 9 4 2 2 9 6 5 1 3
9
9
2
8
9
4
2
9
8
0
5
1
5
1
3
6
7
3
Q
Q
TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299
