CX-JS77 SECTION 5 ELECTRICAL ADJUSTMENTS
CD SECTION
Note: 1. CD Block is basically designed to operate without adjustment. Therefore, 2. 3. 4. check each item in order given. Use YEDS-18 (3-702-101-01) unless otherwise indicated. Use an oscilloscope with more than 10M� impedance. Clean the object lens by an applicator with neutral detergent when the signal level is low than specified value with the following checks.
RF signal waveform VOLT/DIV : 200mV TIME/DIV : 500ns
level : 1.3 ± 0.3 Vp-p
S-CURVE CHECK
Oscilloscope CD board TP(FE) TP(VC)
� CD BOARD (Conductor Side) �
Procedure : 1. Connect an oscilloscope to TP (FE) and TP (VC) on the CD board. 2. Press the I/1 button to turn the power ON. 3. Load a disc (YEDS-18) and actuate the focus search. (In consequence of open and close the disc tray, actuate the focus search) 4. Confirm that the oscilloscope waveform (S-curve) is symmetrical between A and B. And confirm peak to peak level within 3 ± 0.5 Vp-p.
S-curve waveform symmetry
TP (VC)
TP (FE) IC101
A within 3 ± 0.5 Vp-p B
TP (RFACO)
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.
Connecting Location: CD board
RFAC LEVEL CHECK
oscilloscope CD board TP(RFACO) TP(VC)
Procedure : 1. Connect an oscilloscope to TP (RFACO) and TP (VC) on the CD board. 2. Press the I/1 button to turn the power ON. 3. Load a disc (YEDS-18) and playback. 4. Confirm that oscilloscope waveform is clear and check if RFAC signal level is correct or not.
Note: Clear RFAC signal waveform means that the shape � � � can be clearly distinguished at the center of the waveform.
