Sony HTC-WX5 Service Manual page 13

Record Bias Adjustment (Deck B)
Procedure:
1. Press the p (CD) button while pressing the DIRECTION
MODE button.
While pressing the p (CD) button, press the ª (TAPE A)
2.
button, set the function to "deck B".
Insert a tape into deck B, press the r REC button, and then
3.
press the ( button to start recording.
4. Mode: Record
INPUT POINT
1) 315 Hz
} 50 mV (–23.8 dB)
2) 10 kHz
blank tape
AF OSC
CS-123
600 Ω
PFJ-1
attenuator
set
5. Mode: Playback
recorded level meter
position PFJ-1
set
output
point
6. Confirm playback the signal recorded in step 2 become
adjustment level as follows.
If these levels do not adjustment level, adjust the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 3
and 4.
Adjustment level: The playback output of 10 kHz level difference
against 315 Hz reference should be ± 1.0 dB.
Adjustment Location: AUDIO board
[AUDIO BOARD] (Component Side)
RV341(Lch),RV441(Rch) RV311(Lch),RV411(Rch)
Record Bias Playback Level (Deck A)
RV301 RV401
RV411
RV441 RV341
RV311
RV301(Lch),RV401(Rch)
Playback Level (Deck B)
Record Level Adjustment (Deck B)
Procedure:
1. Press the p (CD) button while pressing the DIRECTION
MODE button.
While pressing the p (CD) button, press the ª (TAPE A)
2.
button, set the function to "deck B".
Insert a tape into deck B, press the r REC button, and then
3.
press the ( button to start recording.
4. Mode: Record
INPUT POINT
315Hz 50 mV (–23.8 dB)
blank tape
AF OSC
CS-123
600 Ω
attenuator
PFJ-1 set
5. Mode: Playback
recorded level meter
position PFJ-1
set
output
point
6. Confirm playback the signal recorded in step 2 become
adjustment level as follows.
If these levels do not adjustment level, adjust the RV301 (L-
CH) and RV351 (R-CH) on the MAIN board to repeat steps 3
and 4.
Adjustment level: Output point from PFJ-1 playback level: 47.2
to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location: MAIN board
[MAIN BOARD] (Component Side)
RV301
CNS102
Record
Level (L ch)
CNP105
RV351
CNS101
Record
Level (R ch)
CD SECTION
Note:
1. CD Block is basically constructed 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 10MΩ 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
oscilloscope
BD board
TP (FEO)
TP (VC)
Procedure :
1. Connect oscilloscope to test point TP (FEO).
2. Connect between test point TP (FOK) and Ground by lead wire.
3. Turn Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and
actuate the focus search. (actuate the focus search when disc
table is moving in and out.)
5. Check the oscilloscope waveform (S-curve) is symmetrical
between A and B. And confirm peak to peak level within 3 ±
1Vp-p.
S-curve waveform symmetry
A
B
6. After check, remove the lead wire connected in step 2.
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 bright-
ness to obtain best waveform.
RF Level Check
oscilloscope
BD board
TP (RF)
TP (VC)
Procedure :
1. Connect oscilloscope to test point TP (RF) on BD board.
2. Turned 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.
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.3 ± 0.3 Vp-p
13 13
E-F Balance (1 Track Jump) check
BD board
TP (TEO)
TP (VC)
Procedure:
1. Connect oscilloscope to test point TP (TEO) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Press the "P (Pause)" button.
5. Check the level B of the oscilloscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following:
• A/B x 100 = less then ± 7 (%)
• B = 500 ± 100 mVp-p
1 track jump waveform
0V
level : 500 mV ± 100 mVp-p
Adjustment Location:
Within 3 ± 1 Vp-p
[BD BOARD] (Conductor Side)
TP (RF)
TP
(VC)
TP
(FOK)
IC101
TP
(TEO)
TP
(FEO)
TP
(GND)
IC103
IC102
HTC-WX5
oscilloscope
Center of the waveform
B
A (DC voitage)
Symmetry
IC102