HCD-LX7/LX8
SECTION 6
DIAGRAMS
E-F Balance (1 Track Jump) check6-1. CIRCUIT BOARDS LOCATION
CD SECTION
oscilloscope
Note:SUB TRANS board (LX7)
BD board
1. CD Block is basically constructed to operate without adjustment.
TUNER UNIT
Therefore, check each item in order given.
TP (TE)+
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.TP (VC)�
PANEL-FL board
3. Use an oscilloscope with more than 10M& impedance.
4. Clean the object lens by an applicator with neutral detergent when
the signal level is low than specified value with the followingProcedure:
checks.1. Connect oscilloscope to test point TP (TE) on BD board.
2. Press the "/1 button to turn the unit ON.
S Curve Check3. Put disc (YEDS-18) in to play the number five track.
oscilloscope
4. Press the HX button.
BD board
5. Check the level B of the oscilloscope's waveform and the A (DC
voltage) of the center of the Traverse waveform.
TP (FE)+
Confirm the following:MIC board
TP (VC)�
Y A/B x 100 = less then ? 22 (%)
Procedure :Y B = 1.3 ? 0.6 Vp-p
TRANS board
1. Connect the oscilloscope to test points TP (FE) and TP (VC).TC-A boardMAIN board
1 track jump waveform
2. Connect TP (FE1) and GND, and TP (AGCCON) and GND of
the BD board with lead wires.
3. Press the "/1 button to turn the set ON.Center of the waveform
4. With the disc (YEDS-18) loadedHX, press the button and
perform focus search. (Focus search will be performed in the
same way even while the disc table is pushed in and out.)BPANEL-VR board
5. Check the symmetry and peak to peak level of the oscilloscope
A (DC voitage)
waveform (S curve) at this time.0VTC-B board
HEADPHONE board
S-curve waveform
symmetrySymmetry
level : 1.3 ? 0.6 Vp-p
A
Adjustment Location :
Within 3 ? 1 Vp-p
B
[ BD BOARD ] N SIDE A N
6. After check, remove the lead wire connected in step 2.
CD-L board
Note: Y Try to measure several times to make sure than the ratio ofPA board
A : B or B : A is more than 10 : 7.
Y Take sweep time as long as possible and light up the bright-
CD-R board
ness to obtain best waveform.FRONT INPUT board
TP
(VC)
TABLE SENSOR board
RF Level Check
oscilloscope
BD board
TPLEAF SW board
TP (RF)+(RF)
TP (VC)�
TP
Procedure :(AGCCON)
1. Connect oscilloscope to test point TP (RF) and TP (VC) on BD
board.TP (FE)AUDIO board
2. Press the "/1 button to turn the set ON.TP
TPBD board
3. Put disc (YEDS-18) in and playback 5 track.(TE)
(FE1)
4. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
Note:Clear RF signal waveform means that the shape OE� can be
clearly distinguished at the center of the waveform.
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
CD MOTOR board
level : 1.45 ? 0.25 Vp-p
LED board
1717 |
ACEC
