38
CD SECTION
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M
Ω
impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
S-Curve Check
Procedure :
1. Connect oscilloscope to TP (FEO).
2. Connect between TP (FEI) and TP (VC) by lead wire.
3. Connect between TP (AGCCON) and TP (GND) by lead wire.
4. Turn Power switch on.
5. Load a disc (YEDS-18) and actuate the focus search. (In
consequence of open and close the disc tray, actuate the focus
search)
6. Confirm that the oscilloscope waveform (S-curve) is
symmetrical between A and B. And confirm peak to peak level
within 4 ±1 Vp-p.
7. After check, remove the lead wire connected in step 2 and 3.
Note :
• Try to measure several times to make sure than the ratio
of A : B or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the
brightness to obtain best waveform.
RF Level Check
Procedure :
1. Connect oscilloscope to TP (RF).
2. Connect between TP (AGCCON) and TP (GND) by lead wire.
3. Turned Power switch on.
4. Load a disc (YEDS-18) and playback.
5. Confirm that oscilloscope waveform is clear and check RF signal
level is correct or not.
6. After check, remove the lead wire connected in step 2.
BD (CD) board
Oscilloscope
TP(FEO)
TP(VC)
symmetry
S-curve waveform
within 4
±
1Vp-p
A
B
TP(RF)
TP(VC)
BD board
oscilloscope
Note:
Clear RF signal waveform means that the shape “
◊
” can be
clearly distinguished at the center of the waveform.
RF signal waveform
E-F Balance (1 Track jump) Check
Procedure:
1. Connect oscilloscope to TP (TEO) and TP (VC) board.
2. Turned Power switch on.
3. Load a disc (YEDS-18) and playback the number five track.
4. Press the
u
button. (Becomes the 1track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.
1 track jump waveform
Specification level:
x
100=less than ±22%
6. After check, remove the lead wire connected in step 1.
RF PLL Free-run Frequency
Procedure :
1. Connect frequency counter to test point (XPCK) with lead wire.
2. Turned Power switch on.
3.
Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218MHz.
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.45
±
0.3Vp-p
oscilloscope
BD (CD) board
TP (TEO)
TP (VC)
+
–
0V
Center of
waveform
B
Symmetry
A (DC voltage)
level=1.3
±
0.6Vp-p
A
B
+
–
frequency counter
BD (CD) board
TP (XPCK)
Содержание HCD-ZX50MD
Страница 9: ...9 BD CD BOARD To repair the BD CD board remove the bottom plate Bottom view ...
Страница 39: ...39 Adjustment Location BD CD BOARD SIDE B TP VC TP RF TP TEO TP FEO TP GND TP AGCCON IC102 TP XPCK ...
Страница 66: ...HCD ZX50MD 66 66 7 11 SCHEMATIC DIAGRAM MAIN 1 4 SECTION See page 65 for Printed WIring Board ...
Страница 67: ...HCD ZX50MD 67 67 7 12 SCHEMATIC DIAGRAM MAIN 2 4 SECTION See page 65 for Printed WIring Board ...
Страница 75: ...HCD ZX50MD 75 75 7 20 SCHEMATIC DIAGRAM AMP US AEP UK G AED CIS model SECTION ...
Страница 77: ...HCD ZX50MD 77 77 7 22 SCHEMATIC DIAGRAM AMP E MX AR HK MY SP KR AUS model SECTION ...
Страница 81: ...HCD ZX50MD 81 81 7 26 SCHEMATIC DIAGRAM SWITCH SECTION ...
Страница 83: ...HCD ZX50MD 83 83 7 28 SCHEMATIC DIAGRAM CD MECHANISM SECTION 09 Page 68 Page 68 R S ...
Страница 87: ...HCD ZX50MD 87 87 7 34 SCHEMATIC DIAGRAM POWER SUPPLY US AEP UK G AED CIS model SECTION T6 3AL T6 3AL 125V ...
Страница 89: ...HCD ZX50MD 89 89 7 34 SCHEMATIC DIAGRAM POWER SUPPLY E MX AR HK MY SP KR AUS model SECTION AUS 250V 250V 250V ...
Страница 116: ...116 MEMO ...