Sony HCD-LV80 / LBT-LV80 Service Manual ▷ View online
17
Record Bias Adjustment (Deck B)
Procedure:
INTRODUCTION
When set to the test mode performed in
When set to the test mode performed in
Tape Speed Adjust-
ment
,
when the tape is rewound after recording, the “REC memory
mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO 1.
(After recording, press the m button without stopping will re-
turn to the position where recording was started.)
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO 1.
(After recording, press the m button without stopping will re-
turn to the position where recording was started.)
1. Press FUNCTION button to select VIDEO 1. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B, press the z REC button, and then
press the H button to start recording.
3. Mode: Record
5. Confirm playback the signal recorded in step 2 become adjust-
ment 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.
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
Record Level Adjustment (Deck B)
Procedure:
INTRODUCTION
When set to the test mode performed in
When set to the test mode performed in
Tape Speed Adjust-
ment
, when the tape is rewound after recording, the “REC memory
mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this
adjustment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO 1.
(After recording, press the m button without stopping will re-
turn to the position where recording was started.)
set.
This “REC memory mode” is convenient for performing this
adjustment. During recording, the input signal FUNCTION will au-
tomatically switch to VIDEO 1.
(After recording, press the m button without stopping will re-
turn to the position where recording was started.)
1. Press FUNCTION button to select VIDEO 1. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B, press the z REC button, and then
press the H button to start recording.
3. Mode: Record
4. Mode: Playback
5. Confirm playback the signal recorded in step 2 become adjust-
ment 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.
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:
CN301 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)
CN301 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location: MAIN board
Adjustment Location:
[AUDIO BOARD] (Conductor Side)
4. Mode: Playback
[MAIN BOARD] (Conductor Side)
recorded
position
position
level meter
set
main board
CN301
Pin
CN301
Pin
1
(R-ch)
Pin
3
(L-ch)
AF OSC
VIDEO 1 (AUDIO) IN
1) 315 Hz
2) 10 kHz
1) 315 Hz
2) 10 kHz
blank tape
CS-123
CS-123
set
attenuator
600
Ω
} 50 mV (–23.8 dB)
AF OSC
VIDEO 1 (AUDIO) IN
315Hz 50 mV (–23.8 dB)
315Hz 50 mV (–23.8 dB)
blank tape
CS-123
CS-123
set
attenuator
600
Ω
recorded
position
position
level meter
set
main board
CN301
Pin
CN301
Pin
1
(R-ch)
Pin
3
(L-ch)
Record Level (Lch)
RV301
RV301
RV351
Record Level (Rch)
Record Level (Rch)
IC301 1
14 15
28
29
42
43
56
3
1
1
CN301
RV441 RV341
RV301(Lch),RV401(Rch)
Playback Level (Deck B)
Playback Level (Deck B)
RV301 RV401
RV341(Lch),RV441(Rch)
Record Bias
Record Bias
RV311(Lch),RV411(Rch)
Playback Level (Deck A)
Playback Level (Deck A)
RV311
RV411
18
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 10M
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.
checks.
S Curve Check
Adjustment Location: BD board
Procedure :
1. Connect the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FEI) and GND, and TP (AGCCON) and GND of
1. Connect the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FEI) and GND, and TP (AGCCON) and GND of
the BD board with lead wires.
3. Press the "/1 button to turn the set ON.
4. With the disc (YEDS-18) loaded, press the 7 button and
4. With the disc (YEDS-18) loaded, press the 7 button and
perform focus search. (Focus search will be performed in the
same way even while the disc table is pushed in and out.)
same way even while the disc table is pushed in and out.)
5. Check the symmetry and peak to peak level of the oscilloscope
waveform (S curve) at this time.
S-curve waveform
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.
Adjustment Location: BD board
RF Level Check
Procedure :
1. Connect oscilloscope to test point TP (RF) and TP (VC) on BD
1. Connect oscilloscope to test point TP (RF) and TP (VC) on BD
board.
2. Connect TP (AGCCON) and GND of the BD board with lead
wires.
3. Press the "/1 button to turn the set ON.
4. Put disc (YEDS-18) in and playback 5track.
5. Confirm that oscilloscope waveform is clear and check RF sig-
4. Put disc (YEDS-18) in and playback 5track.
5. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
6. After check, remove the lead wire connected in step 2.
oscilloscope
BD board
TP (FE)
TP (VC)
TP (VC)
+
–
–
oscilloscope
BD board
TP (RF)
TP (VC)
TP (VC)
+
–
–
E-F Balance (Traverse) Check
oscilloscope
BD board
TP (TE)
TP (VC)
TP (VC)
+
–
–
Adjustment Location: BD board
Procedure :
1. Connect oscilloscpe to test point TP (TE) on BD board.
2. Short-circuit SL502 of the video board to GND.
3. Turned Power switch on. Press FUNCTION button to select
1. Connect oscilloscpe to test point TP (TE) on BD board.
2. Short-circuit SL502 of the video board to GND.
3. Turned Power switch on. Press FUNCTION button to select
CD.
4. Put disc (YEDS-18) in to play the number five track.
5. Press the PLAY MODE button. (The tracking servo and the
5. Press the PLAY MODE button. (The tracking servo and the
sledding servo are turned OFF.)
6. Check the level B of the oscilliscope's waveform and the A (DC
voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 22%
Confirm the following :
A/B x 100 = less than ± 22%
Traverse waveform
0V
level : 1.3
±
0.6 Vp-p
A (DC voltage)
Center of the waveform
B
7. Press the PLAY MODE button. (The tracking servo and sled-
ding servo are turned ON.) Confirm the C (DC voltage) is al-
most equal to the A (DC voltage) is step 7.
most equal to the A (DC voltage) is step 7.
Traverse waveform
0V
C (DC
voltage)
voltage)
Tracking servo
Sled servo
OFF
Sled servo
OFF
Tracking servo
Sled servo
ON
Sled servo
ON
symmetry
A
B
Within 4.0
±
1.0 Vp-p
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
TIME/DIV : 500ns
level : 1.75
±
0.25 Vp-p
8. Desolder the short-land (SL502) short-circuited at step 2.
Adjustment Location: BD board
HCD-LV80
19
19
SECTION 7
DIAGRAMS
VIDEO SECTION
Frequency adjustment
1. Connect the frequency counter to check point of the VIDEO
board.
2. Adjust CT503 of the VIDEO board so that the frequency counter
read 27MHz ± 80Hz at STOP condition.
[ VIDEO BOARD ] – SIDE B –
Adjustment Location :
[ VIDEO BOARD ] – SIDE A –
frequency counter
VIDEO board
(27 MHz)
(27 MHz)
+
–
–
SL501
IC502
IC506
(27MHz)
(GND)
SL502
SL503
TEST
MODE
SL501
D502
SL502
CT503
SL503
TEST MODE
VIDEO
FREQUENCY
(27MHz)
(GND)
IC507
IC505
Adjustment Location :
[ BD BOARD ] — SIDE B —
TP
(VC)
(VC)
TP
(RF)
(RF)
TP
(TE)
(TE)
TP
(IOP)
(IOP)
TP
(FE)
(FE)
TP
(AGCCON)
(AGCCON)
7-1. CIRCUIT BOARDS LOCATION
BD board
MIC board
TC-A board
TC-B board
PANEL-FL board
PANEL-VR board
HEADPHONE board
LED board
CD MOTOR board
TABLE SENSOR board
TUNER UNIT
TRANS board
MAIN board
FRONT INPUT board
CD-R board
CD-L board
PA board
AUDIO board
LEAF SW board
VIDEO board
HCD-LV80
20
20
E
F
A
B
C
D
DRIVE
Q101
LD
RF EQ
AMP
SUMMING
AMP
RF
ERROR
AMP
FOCUS
ERROR
AMP
TRACKING
APC LD
AMP
VC
BUFFER
VC
REF
RF AMP
IC103
DIGITAL SERVO
DIGITAL SIGNAL PRCESSOR
IC101
IC781
LASER
DIODE
DETECTOR
OPTICAL PICK-UP BLOCK
(KSS-213D/Q-NP)
A
C
D
B
E
F
LD
POWER
PD
LD
PD
LD
A
C
D
B
E
F
TE
FE
RFD
RFI
ASYMMETRY
CORRECTION
AUTO
SEQUENCER
SERVO
INTEG-
RATOR
DIGITAL
PLL
EFM
DEMODULATOR
REGISTER
SUB CODE
PROCESSOR
ERROR
CORRECTOR
DATA BUS
32K
RAM
D/A
INTERFACE
DIGITAL
CD DIGITAL
OUT
OPTICAL
OUT
DOUT
SERVO
INTERFACE
DIGITAL
CLV
LD ON
OP AMP
ANALOG SW
A/D
CONVERTER
PWM
GENERATOR
TRACKING
PWM
GENERATOR
FOCUS
PWM
GENERATOR
SLED
PWM
GENERATOR
VC
TRACKING
SERVO
FOCUS
SERVO
SLED
SERVO
SERVO DSP
TFDR
TRDR
FFDR
FRDR
SFDR
SRDR
MDP
DETECTOR
MIRR
DFCT
FOK
D OUT
PCM-D
S STOP
RFDC
FE
TE
CE
VC
SE
CPU
INTERFACE
SENS
DATA
XLAT
CLOK
CLOCK
GENERATOR
XTAI
XTSL
M
M
TRACKING
COIL
FOCUS
COIL
SLED
MOTOR
M102
SPINDLE
MOTOR
M101
T+
T
F+
F
SD+
SD
SP+
SP
FOCUS/TRACKING COIL DRIVE
SPINDLE/SLED MOTOR DRIVE
IC102
VC
TFDR
TRDR
FFDR
FRDR
SFDR
SRDR
XRST
MUTE
09
S101
LIMIT SW
SQCK
A+5V
IC104
XRST
ADATA
BCLK
LRCK
MCK
SENS
CTRL1
DATA
SCLK
SCLK
XLT
CLK
SCOR
SQSO
SCOR
SUBQ
SQCK
LPH
XRST
LD ON
LRCK
BCLK
C2PO
MUTE
MUTE
C2PO
D+5V
MD2
RF AC
ASYI
ASYO
CONTROL SIGNAL
BLOCK
SERVO
BLOCK
VCC
VC
VIDEO
SECTION
• SIGNAL PATH
: CD
: VIDEO
: Digital out
(Page 24)
MAIN
SECTION (2/2)
(Page 23)
A
C
(XTAL 33.8MHz)
4
2
5
7
8
6
11
10
3
4
23
24
27
25
20
22
21
12
13
17
14
16
50
48
49
43
38
41
39
40
42
32
31
34
33
30
29
25
64
63
67
66
14
65
71
3
7
69
15
6
5
4
77
76
8
26
82
1
12
11
14
13
17
18
15
16
3
2
6
5
INTEG-
RATOR
TBL-R
UP SW
TRAY SENS
TBL-L
DISC
SENSOR
IC202
IC201
MOTOR DRIVER
3
7
OUT 2
OUT 1
1
IN 2
9
IN 1
M
+5V
M201
TABLE
MOTOR
LED
D201
(DISC No.)
LED SW
Q201
S201
(UP SWITCH)
7-2. BLOCK DIAGRAMS
– BD SECTION –
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