Table of Contents
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| CDP-X339ES
SECTION
2
ELECTRICAL BLOCK CHECKING
Note:
1.
CD Block basically constructed to operate without adjus-
tment.
Therefore, check each item in order given.
2.
Use YEDS-18 disc (3-702-101-01) unless otherwise indicat-
ed.
3.
Use the oscilloscope with more than 10MQ impedance.
4.
Clean an object lens by an applicator with neutral deter-
gent when the signal level is low than specified value
with the following checks.
S Curve Check
oscilloscope
BD board
C)
earl
et
TP(FE)
Soe
pk
TP(VC)
O—t———0 -
Procedure :
1.
Connect oscilloscope to test point TP (FE) on BD board.
2.
Connect between test point TP (FEI) and TP (VC) with
lead wire.
3.
Turned Power switch on and actuate the focus serch.
(actuate the focus serch when disc table is moving in and
out.)
4.
Check the oscilloscope waveform (S curve) is symmetri-
cal between A and B. And confirm peak to peak level
within 3+1Vp-p.
S curve waveform
symmetry
within
3 +1Vpp
5.
After check, remove the lead wire connected in step 2.
Note: @ Try to mesure several times to make sure that the
ratio of
A: B or B:
A is more than 10:
7.
e Take sweep time as long as possible and light up the
brightness to obtain best waveform.
RF Level Check
oscilloscope
BD board
C)
enr—
TP(RF) O«—OF
TP(VC) O=t—70 -
Procedure :
1.
Connect oscilloscope to test point TP (RF) on BD board.
2.
Turn Power switch on.
3.
Put disc (YEDS-18) in and playback.
4.
Confirm that oscilloscope waveform
is clear and check
RF signal level is correct or not.
Note:
Clear RF signal waveform means that the shape "<>" can be
clearly distinguished at the center of the waveform.
VOLT/DIV:
200mV
RF signal waveform
TIME/DIV:
500nS
iii Wise A
\ RE
[RRR
NY
OS)
level:
a 1.2 207 Vp-p
E-F Balance Check
oscilloscope
BD board
C)
———
TP(TE)
O<=———o +
TP(VC) Owe—lo -
Procedure :
1.
Connect test point TP (ADJ) to ground and TP (TEI) to
TP (VC) with lead wires.
2.
Connect oscilloscope to test point TP (TE) on BD board.
3.
Turn Power switch on.
4.
Put disc (YEDS-18) in and playback.
5.
Confirm that the osilloscope waveform is symmetrical on
the top and bottom in relation to 0V, and check this level.
Traverse oscilloscope
wah
Ma
oy
eal
an
int
tit 14
symmetry
level: 2£1Vpp
6.
Remove the lead wires connected in step 1.
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