Sony HCD-V919AV User manual

MICROFILM
SERVICE MANUAL
MINI Hi-Fi COMPONENT SYSTEM
E Model
Chinese Model
SPECIFICATIONS
HCD-V919AV
This stereo system is equipped with the Dolby B-
type noise reduction system and Dolby Pro Logic
Surround decoder*.
* Manufactured under license from Dolby Labora-
tories Licensing Corporation.
DOLBY, the double-D symbol aand“PRO LOGIC”
aretrademarksofDolbyLaboratoriesLicensingCor-
poration.
HCD-V919AV is the Amplifier, Video CD
player, Tape Deck and Tuner section in
MHC-V919AV.
Model Name Using Similar Mechanism HCD-V717
CD Mechanism Type CDM38L-5BD24AL
Base Unit Name BU-5BD24AL
Optical Pick-up Name KSS-213D/Q-NP
Model Name Using Similar Mechanism HCD-V717
Tape Transport Mechanism Type TCM-230AWR1/
230PWR1
CD
Section
Tape
Deck
Section
– Continued on next page –

– 2 –
TABLE OF CONTENTS
1. SERVICING NOTES.............................................. 3
2. GENERAL .................................................................. 6
3. DISASSEMBLY ........................................................ 10
4. TEST MODE............................................................. 13
5. MECHANICAL ADJUSTMENTS...................... 16
6. ELECTRICAL ADJUSTMENTS
DECK Section................................................................ 16
CD Section ..................................................................... 19
VIDEO Section .............................................................. 21
7. DIAGRAMS
7-1. Block Diagram – SERVO Section –............................. 23
7-2. Block Diagram – AUDIO/VIDEO CD Section – ........ 25
7-3. Block Diagram – TAPE DECK Section – .................... 27
7-4. Block Diagram – MAIN Section (1/2) –...................... 29
7-5. Block Diagram – MAIN Section (2/2) –...................... 31
7-6. Block Diagram – DISPLAY/KEY CONTROL/
POWER SUPPLY Section – .......................................... 33
7-7. Note for Printed Wiring Boards and
Schematic Diagrams ...................................................... 36
7-8. Printed Wiring Board – BD Section – .......................... 37
7-9. Schematic Diagram – BD Section –............................ 39
7-10. Printed Wiring Board – VIDEO Section – ................... 41
7-11. Schematic Diagram – VIDEO Section (1/2) – ............ 43
7-12. Schematic Diagram – VIDEO Section (2/2) –............ 45
7-13. Printed Wiring Boards – CD MOTOR Section –......... 47
7-14. Schematic Diagram – CD MOTOR Section – ............ 49
7-15. Printed Wiring Board – TAPE DECK Section –.......... 51
7-16. Schematic Diagram – TAPE DECK Section –............ 53
7-17. Printed Wiring Board – LEAF SW Section – .............. 55
7-18. Schematic Diagram – LEAF SW Section – ................ 55
7-19. Printed Wiring Board – MAIN Section –..................... 57
7-20. Schematic Diagram – MAIN Section (1/4) –.............. 59
7-21. Schematic Diagram – MAIN Section (2/4) –............... 61
7-22. Schematic Diagram – MAIN Section (3/4) –............... 63
7-23. Schematic Diagram – MAIN Section (4/4) –............... 65
7-24. Printed Wiring Board – PANEL Section – ................... 67
7-25. Schematic Diagram – PANEL Section – ...................... 69
7-26. Printed Wiring Boards – DISPLAY Section – ............. 71
7-27. Schematic Diagram – DISPLAY Section –................. 73
7-28. Schematic Diagram
– MIC/HEADPHONE Section – ................................... 75
7-29. Printed Wiring Boards
– MIC/HEADPHONE Section – ................................... 76
7-30. Printed Wiring Board – POWER AMP Section – ........ 77
7-31. Schematic Diagram – POWER AMP Section – ........... 79
7-32. Schematic Diagram
– TRANSFORMER Section –....................................... 81
7-33. Printed Wiring Board
– TRANSFORMER Section –....................................... 83
7-34. Printed Wiring Board – SURROUND Section – ......... 84
7-35. Schematic Diagram – SURROUND Section – ............ 85
7-36. IC Pin Function Description .......................................... 94
8. EXPLODED VIEWS............................................... 106
9. ELECTRICAL PARTS LIST .............................. 114

– 3 –
SELF-DIAGNOSIS
This unit is equipped with a self-diagnosis function.
The function is used for diagnosing the conditions of the circuits
of the VIDEO board.
The circuits can be determined if normal or abnormal by the light-
ing of D502 of the VIDEO board.
Lighting of D502
When lit : Operates normally
Blinks repeatedly: The circuit may be faulty.
[VIDEO Board] (Side A)
D502
IC505
SECTION 1
SERVICING NOTES
The laser diode in the optical pick-up block may suffer electro-
static break-down because of the potential difference generated
by the charged electrostatic load, etc. on clothing and the human
body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused
on the disc reflective surface by the objective lens in the optical
pick-up block. Therefore, when checking the laser diode emis-
sion, observe from more than 30 cm away from the objective lens.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-
aged by heat.
Flexible Circuit Board Repairing
• Keep the temperature of the soldering iron around 270 ˚C dur-
ing repairing.
• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
• Be careful not to apply force on the conductor when soldering
or unsoldering.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra-
diation exposure.
This appliance is classified as a CLASS 1 LASER product.
The CLASS 1 LASER PRODUCT MARKING is located on
the rear exterior.
Laser component in this product is capable of emitting radiation
exceeding the limit for Class 1.
The following caution label is located inside the unit.
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK !OR DOTTED
LINE WITH MARK !ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFE
OPERATION. REPLACE THESE COMPONENTS WITH
SONY PARTS WHOSE PART NUMBERS APPEAR AS
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.

– 4 –
MODEL IDENTIFICATION
– Back Panel –
PART No.
MODEL PART No.
Malaysia and Singapore models 4-900-722-0π
Chinese model 4-900-722-1π
Indonesia model 4-900-722-2π
Thai model 4-900-722-3π
IC502 OF VIDEO BOARD
IC502 of the VIDEO board consists of the former type and new
type. The following table shows the differences between the two
types.
Only spare parts for the new type IC502 are supplied.
Units using the former IC502 will not function when replaced with
the new type without performing the following procedure.
Consequently, replace IC502 of units using the former type ac-
cording to the following procedure.
Table of Differences
Replacing Procedure
1. Remove IC402.
2. Solder JW421 and JW422, or short-circuit with a lead wire,
etc.
3. Replace IC502 with a new one.
How to Differentiate
[VIDEO board] (Side A)
FORMER TYPE NEW TYPE
C407, 408 MOUNT NO MOUNT
IC502 M30620MC-302FP M30620MC-305FP
JW421, JW422 NO MOUNT MOUNT
IC402 MOUNT NO MOUNT
R413, 421, 422 MOUNT NO MOUNT
X401 MOUNT NO MOUNT
Those with IC402 : FORMER TYPE
Those without IC402: NEWTYPE

– 5 –
HOW TO OPEN THE DISC TRAY WHEN POWER SWITCH
TURNS OFF
NOTE FOR INSTALLATION (ROTARY ENCODER)
3 pull-out the disc tray.
1 Remove the case.
2 Turn the cam to the
direction of arrow.
BU cam
groove section A
Note: When attaching the Base unit, Insert th
e
section A into the groove of BU cam.
Note:When attaching the BU cam,
engage the Rotary encoder
switch as shown in the figure.

– 6 –
SECTION 2
GENERAL
LOCATION OF CONTROLS
• Front view
11/u(POWER) button
2DISC 1 button and indicator
3DISC 2 button and indicator
4DISC 3 button and indicator
5DISC SKIP/EX-CHANGE button
6§button
7Disc tray
8Decoration
9§button (Deck B)
0Deck A 9, (buttons and indicators
!¡ Deck B 9, (buttons and indicators
!™ CD ^button and indicator
!£ TUNER, BAND button
!¢ PRO LOGIC button and indicator
!∞ DSP button and indicator
!§ KARAOKE PON/MPX button
!¶ GROOVE button and indicator
!• VOLUME knob
!ª PHONES jack
@º DBFB button
@¡ –, 0button and indicator
@™ ENTER/NEXT button and indicator
@£ pbutton
@¢ AUTO BPM button and indicator
@∞ +, )button and indicator
@§ BEAT, JAM button and indicator
@¶ BEAT, SPEED button
@• BEAT, SELECT button
@ª BEAT, ON/OFF button and indicator
#º P FILE MEMORY button
#¡ GEQ CONTROL button
#™ FILE SELECT button
#£ EFFECT button and indicator
#¢ FUNCTION button
#∞ §button (Deck A)
1 2 3 4 5
7
6
8
9
0
!¡
!™
!£
!¢
!∞
!§
!¶
!•
!ª
@£ @™ @¡@¢@∞@§@¶
#£
#™
#¡
#º
@ª
@•
#¢
#¢
@º

– 7 –
#§ Display window
#¶ PBC OFF indicator
#• PBC indicator
#ª VIDEO CD indicator
$º PLAY MODE, DOLBY NR,
TUNER MEMORY button
$¡ EDIT, DIRECTION button
$™ REPEAT, STEREO/MONO button
$£ rREC button and indicator
$¢ PPAUSE button and indicator
$∞ HI-DUB button
$§ CD SYNC button
$¶ NEXT button
$• PREV button
$ª RETURN button
%º SELECT button
%¡ ACTIVE button
%™ JOG dial
%£ BEAT LEVEL button
%¢ PAD B button
%∞ PAD A button
%§ MIC 2 jack
%¶ MIC 1 jack
%• MIC LEVEL knob
%ª ECHO LEVEL knob
^º DEMO button
^¡ DISPLAY button
^™ CLOCK/TIMER SET button
^£ TIMER/SELECT button
^¢ CD LOOP button
^∞ CD FLASH button
^§ CD NON-STOP button and indicator
#§
$¡
$º
#ª
#•
#¶
$™
$£
$¢
$§
$∞
%™ $ª $• $¶%º%¡%¢%∞
^™
^¡
^º
%ª
%•
%§
%¶
^£
^¢
^∞
^§
%£

– 8 –
1S VIDEO OUT jack
2SYSTEM SELECT switch
3VIDEO OUT jack
4FM antenna terminal
5AM antenna terminals
6VOLTAGE SELECTOR switch
7SURROUND SPEAKER, CENTER terminals
8SURROUND SPEAKER, REAR terminals
9FRONT SPEAKER terminals
0SUPER WOOFER jack
!¡ MD OUT jacks
!™ MD IN jacks
!£ VIDEO (AUDIO) IN jacks
!¢ CD DIGITAL OUT, OPTICAL connector
1 2 3
4
5
6
!¢
0
!£
!¡
!™
789
• Rear view

– 9 –
This section is extracted from
instruction manual.

– 10 –
LOADING PANEL
FRONT PANEL
Note: Follow the disassembly procedure in the numerical order given.
SECTION 3
DISASSEMBLY
4 loading panel
3 two claws
2 Pull-out the disc tray.
1 Turn the cam to the direction
of arrow.
1 three screws
(BVTP3 × 8)
5 front panel assembly
2 screw
(BVTP3 × 10)
2 screw
(BVTP3 × 10)
3 connector
(CN203)
3 connector
(CN752)
4 flat type wire
(CN101)
4 flat type wire
(CN106)
4 flat type wire
(CN107)

– 11 –
CASSETTE MECHANISM DECK
PANEL BOARD AND CONT-PANEL BOARD
1 two screws
(BVTT2
× 4)
1 two screws
(BVTT2
× 4)
6 three screws
(BVTP2.6
× 8)
6 two screws
(BVTP2.6
× 8)
8 two screws
(BVTP2.6
× 8)
6 screw
(BVTP2.6
× 8)
6 screw
(BVTP2.6
× 8)
9 bracket
7 mechanism deck
2 damper, oil
2 damper, oil
3 Push the cassette lids.
4 Remove the cassette lids.
5 spring
5 spring
1 ten screws
(BVTP2.6
× 8)
1 three screws
(BVTP2.6
× 8
)
9 four screws
(BVTP2.6
× 8)
9 six screws
(BVTP2.6
× 8)
2 PANEL board
0 CONT-PANEL board
3 shield
4 flat type wire
(CN602)
5 konb (Jog)
6 nut
8 nut
7 konb
(Volume)

– 12 –
DISC TRAY
claw B
claw A
1
Turn the cam the
direction of arrow.
2 Pull-out the disc tray.
5 Remove the disc tray.
4 two claws
3 flat type wire (8 core)
Note: When installing the Disc tray, pull around the flat type wire to
pass through the claw
A and claw B , as shown in the figure.
(Perform after removing the front panel.)

– 13 –
SECTION 4
TEST MODE
[MC Cold Reset]
• The cold reset clears all data including preset data stored in the
RAM to initial conditions. Execute this mode when returning
the set to the customer.
Procedure:
1. Press three buttons p, [ENTER/NEXT], and I/usimulta-
neously.
2. The fluorescent indicator tube becomes blank instantaneously,
and the set is reset.
[CD Delivery Mode]
• This mode moves the pick-up to the position durable to vibra-
tion. Use this mode when returning the set to the customer after
repair.
Procedure:
1. Press I/ubutton to turn the set ON.
2. Press [CDLOOP] button and I/ubutton simultaneously.
3. A message “LOCK” is displayed on the fluorescent indicator
tube, and the CD delivery mode is set.
[MC Hot Reset]
• This mode resets the set with the preset data kept stored in the
memory. The hot reset mode functions same as if the power
cord is plugged in and out.
Procedure:
1. Press three buttons p, [ENTER/NEXT], and [DISC1] simul-
taneously.
2. The fluorescent indicator tube becomes blank instantaneously,
and the set is reset.
[Sled Servo Mode]
• This mode can run the CD sled motor freely. Use this mode, for
instance, when cleaning the pick-up.
Procedure:
1. Press I/ubutton to turn the set ON.
2. Select the function “CD”.
3. Press three buttons p, [ENTER/NEXT], and §simulta-
neously.
4. The Sled Servo mode is selected, if “CD” is blanking on the
fluorescent indicator tube.
5. With the CD in stop status, press )+ button to move the
pick-up to outside track, or – 0button to inside track.
6. To exit from this mode, perform as follows:
1) Move the pick-up to the most inside track.
2) Press three buttons in the same manner as step 3.
Note: • Always move the pick-up to most inside track when exiting from
this mode. Otherwise, a disc will not be unloaded.
• Do not run the sled motor excessively, otherwise the gear can be
chipped.
[Change-over of MW Tuner Step between 9 kHz and
10 kHz]
• A step of MW channels can be changed over between 9 kHz
and 10 kHz.
Procedure:
1. Press I/ubutton to turn the set ON.
2. Select the function “TUNER”, and press [TUNERBAND]
button to select the BAND “MW”.
3. Press I/ubutton to turn the set OFF.
4. Press [ENTER/NEXT] and I/ubuttons simultaneously, and
the display of fluorescent indicator tube changes to “MW 9 k
STEP” or “MW 10 k STEP”, and thus the channel step is
changed over.
[LED and Fluorescent IndicatorTube All Lit, Key Check
Mode]
Procedure:
1. Press three buttons p, [ENTER/NEXT], and [DISC2] simul-
taneously.
2. LEDs and fluorescent indicator tube are all turned on.
Press [DISC2] button, and the key check mode is activated.
3. In the key check mode, the fluorescent indicator tube displays
“K 1 J0 V0”. Each time a button is pressed, “K” value in-
creases. However, once a button is pressed, it is no longer taken
into account.
“J” value increases like 1, 2, 3 ... if rotating [JOG] dial in “+”
direction, or it decreases like 0, 9, 8 ... if rotating in “–” direc-
tion.
“V” value increases like 1, 2, 3 ... if rotating [VOLUME] knob
in “+” direction, or it decreases like 0, 9, 8 ... if rotating in
“–” direction.
4. To exit from this mode, press three buttons in the same man-
ner as step 1, or disconnect the power cord.

– 14 –
[Aging Mode]
This mode can be used for checking the operations of the CD player
and tape deck.
• When problems occur:
Aging stops. If currently aging the tape deck, the state when
aging stops will be displayed on the fluorescent display tube.
• When no problems:
Aging continues.
Preparations:
• Set the CD on the DISC 1 tray.
• Insert a commercially available tape for recording (tapes which
contents can be erased, etc.) in decks A and B.
Setting the aging mode:
Press the pbutton, [ENTER/NEXT] button, and
[DISCSKIP/EX-CHANGE] button together. When the aging mode
is set, the CD roulette work blinks. To exit the mode, press the
I/ubutton and turn OFF the power.
Sequence:
The aging mode is executed in the following sequence.
If the function is set to “CD” when the aging mode is set, aging is
performed starting from the CD player. When set to “TAPEA” or
“TAPE B” aging is started from deck A.
If the function is to others aging will not be stated until the func-
tion is switched to CD or TAPE.
Display of status:
• The aging status is displayed on the fluorescent display tube.
(Only when executing the tape deck section.)
• During the aging of the tape deck, the operations performed
will be displayed. If operations ended abnormally, this will be
displayed at the fluorescent indicator tube.
Tape Deck
Display of Operations Operation Timing of Ending
TAPE A AG-1 TAPE A REW Shutoff
TAPE A AG-2 TAPE A FWD 2 minute playback
TAPE A AG-3 TAPEA FF 20 seconds or shutoff
TAPE A AG-4 TAPE A REV 2 minutes playback
TAPE A AG-5 TAPE A REW Shutoff
TAPE B AG-1 TAPE B REW Shutoff
TAPE B AG-2 TAPE B FWD 2 minute playback
TAPE B AG-3 TAPE B FF 20 seconds or shutoff
TAPE B AG-4 TAPE B REV 2 minute playback
TAPE B AG-5 TAPE B REW Shutoff
Aging of CD player (12 minutes)
Aging of deck A
Aging of deck B Maximum about 12 minutes
Operations during aging
• Operations are performed in the following sequence during ag-
ing.
<CD player>
1. The CD tray rotates and disc 1 is selected.
2. Chucking is performed.
3. TOC is read.
4. Track 1 played back for 8 seconds.
5. The CD tray opens and closes again.
6. 1 to 5 is repeated.
7. After 12 minutes of aging, aging is switched to the tape deck.
<Tape Deck>
1. The tape in deck A is rewound to the head.
2. The FWD side is played back for 2 minutes.
3. The tape is fast forwarded (FF) for 20 seconds. The following
procedure is performed when the tape end is reached before
the 20 seconds.
4. The REV side is played back for 2 minutes.
5. The tape is rewound to the head (REW).
6. The tape in deck B is rewound to the head.
7. The FWD side is played back for 2 minutes.
8. The tape is fast forwarded (FF) for 20 seconds. The following
procedure is performed when the tape end is reached before
the 20 seconds.
9. The REV side is played back for 2 minutes.
10. The tape is rewound to the head (REW).
11. Aging is switched to the CD player.

– 15 –
[VIDEO CD Color-bars Mode]
On this mode, the data of the color-bars signal as a picture signal
and the 1 kHz sine wave signal as a sound signal are output by the
mechanism controller (IC502) for the video CD signal check.
When measurement of the voltage and waveform on the VIDEO
board, perform it in this mode.
For reference, the color-bars signal can be observed at J302
(VIDEO OUT) and the sound signal can be observed at J101
(VIDEO/MD (AUDIO) OUT) using an oscilloscope.
Procedure:
1. Connect the lead wire to both ends of the land of SL503 of the
VIDEO board.
2. Turn the power on. Press [FUNCTION] button to select CD.
3. After 2 or 3 seconds later, connect the lead wire.
4. After measuring, remove the lead wire connected.
[VIDEO board] (Side A)
[VIDEO board] (Side B)
D502
SL501
SL503
SL502
IC505
SL503 IC502
CN501
CN503
SL502
SL501

– 16 –
SECTION 5
MECHANICAL ADJUSTMENTS
Mode Torqu Meter Meter Reading
FWD CQ-102C 31 to 71 g•cm
(0.43 – 0.98 oz•inch)
FWD CQ-102C 2 to 6 g•cm
Back Tension (0.02 – 0.08 oz•inch)
REV CQ-102RC 31 to 71 g•cm
(0.43 – 0.98 oz•inch)
REV CQ-102RC 2 to 6 g•cm
Back Tension (0.02 – 0.08 oz•inch)
FF/REW CQ-201B 71 to 143 g•cm
(0.98 – 1.99 oz•inch)
FWD tension CQ-403A 100 g or more
(3.53 oz or more)
REV tension CQ-403R 100 g or more
(3.53 oz or more)
SECTION 6
ELECTRICAL ADJUSTMENTS
Precaution
1. Clean the following parts with a denatured alcohol-moistened
swab:
record/playback heads pinch rollers
erase head rubber belts
capstan idlers
2. Demagnetize the record/playback head with a head demagne-
tizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
Torque Measurement
DECK SECTION 0 dB=0.775 V
Tape Signal Used for
P-4-A100 10 kHz, –10 dB Azimuth Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
P-4-L300 315 Hz, 0 dB Level Adjustment
DECK A DECK B
1. Demagnetize the record/playback head with a head demagne-
tizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in
this service manual. (As a general rule, playback circuit ad-
justment should be completed before performing recording
circuit adjustment.)
6. The adjustments should be performed for both L-CH and R-
CH.
7. Switches and controls should be set as follows unless other-
wise specified.
• Test Tape
Record/Playback Head Azimuth Adjustment
Note: Perform this adjustments for both decks
Procedure:
1. Mode: Playback (FWD)
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
set
MAIN board
CN301
Pin
1 (L-CH)
Pin
3 (R-CH)
MAIN board
CN301
Pin
2 (GND)
+
–
level meter
test tape
P-4-A100
(10 kHz, –10 dB)
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak R-CH
peak
within
1dB
Screw
position
R-CH
peak

– 17 –
3. Mode: Playback (FWD)
4. Repeat setps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the
pats adjusted.
Adjustment Location:Playback Head (Deck A).
Record/Playback/Erase Head (Deck B).
Tape Speed Adjustment DECK B
Note: Start the Tape Speed adjustment as below after setting to the test
mode.
In the test mode, the tape speed is high during pressing the
[HI-DUB] button.
Procedure:
1. Turn the power switch on.
2. Press the pbutton, [ENTER/NEXT] button and [DISC3] button
simultaneously.
(The “VOLUME” on the fluorescent indicator tube will blink
while in the test mode.)
To exit from the test mode, press the I/ubutton.
Mode: Playback
1. Insert the WS-48B into the deck B.
2. Press the ·button on the deck B.
3. Press the [HI-DUB] button in playback mode.
Then at HIGH speed mode.
4. Adjust RV1001 on the LEAF SW board do that frequency
counter reads 6,000 ± 180 Hz.
5. Press the [HI-DUB] button.
Then back to NORMAL speed mode.
6. Adjust RV1002 on the LEAF SW board so that frequency
counter reads 3,000 ± 90 Hz.
Adjustment Location: LEAF SW board
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)
(WS-48B)
Playback level Adjustment DECK A DECK B
Procedure:
Mode: Playback
Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within adjustment
level as follows.
Adjustment Level:
CN301 PB level: 301.5 to 338.3 mV (–8.2 to –7.2 dB) level
difference between the channels: within ± 0.5 dB
Adjustment Location: AUDIO board
set
test tape
P-4-A100
(10 kHz, –10 dB)
(pin
3 : R-CH)
oscilloscope
VH
waveform of oscilloscope
in phase 45 ° 90 ° 135 ° 180 °
good wrong
(pin 2 : GND)
(pin
1 : L-CH)
MAIN board
CN301
Reverse Foward
1 Remove the four claws
2 Window
+
–
set
test tape
WS-48B
(3 kHz, 0 dB)
MAIN board
CN301 (Pin
1 : L-CH)
(
Pin
3
: R-CH
)
frequency counter
+
–
set
test tape
P-4-L300
(315 Hz, 0 dB)
MAIN board
CN301 (Pin
1 : L-CH)
(Pin
3 : R-CH)
level meter

– 18 –
REC Bias Adjustment DECK B
Procedure:
INTRODUCTION
When set to the test mode performed in TapeSpeed Adjustment,
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 au-
tomatically switch to VIDEO.
(After recording, press the – 0button without stopping will
return to the position where recording was started.)
1. Press [FUNCTION] button to select VIDEO. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B.
3. After press [REC] button, press Pbutton, then recording
start.
4. Mode: Record
5. Mode: Playback
6. Confirm playback the signal recorded in step 3 become ad-
justable level as follows.
If these levels do not adjustable level, adjustment the RV341
(L-CH) and RV441 (R-CH) on the AUDIO board to repeat
steps 4 and 5.
Adjustable level: Playback output of 315 Hz to playback output
of 10 kHz: ± 1.0 dB
Adjustment Location: AUDIO board
REC Level Adjustment DECK B
Procedure:
INTRODUCTION
When set to the test mode performed in TapeSpeed Adjustment,
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 au-
tomatically switch to VIDEO.
(After recording, press the – 0button without stopping will
return to the position where recording was started.)
1. Press [FUNCTION] button to select VIDEO. (This step is not
necessary if the above test mode has already been set.)
2. Insert a tape into deck B.
3. After press [REC] button, press Pbutton, then recording
start.
4. Mode: Record
5. Mode: Playback
6. Confirm playback the signal recorded in step 3 become ad-
justable level as follows.
If these levels do not adjustable level, adjustment the RV301
(L-CH) and RV351 (R-CH) on the MAIN board to repeat steps
4 and 5.
Adjustable level:
CN301 PB level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location: MAIN board
Adjustment Location:
[MAIN Board] (Component Side)
[AUDIO Board] (Component Side)
[LEAF SW Board] (Component Side)
r
r
attenuator
+
–+
–+ –set
MD/VIDEO (AUDIO) IN
1) 315 Hz
2) 10 kHz 50 mV (–23.8 dB)



600 Ω
blank tape
CN-123
AF OSC
+
–
set
recorded
portion
MAIN board
CN301 (Pin
1 : L-CH)
(Pin
3 : R-CH)
level mete
r
set
MD/VIDEO (AUDIO) IN
315 Hz, 50 mV (–23.8 dB) blank tape
CS-123
600
Ω
attenuator
AF OSC
+
–+
–+ –
+
–
set
recorded
portion
MAIN board
CN301 (Pin
1 : L-CH)
(Pin
3 : R-CH)
level mete
r
RV301
L
REC LEVEL
RV351
R
IC301 CN301
1 3
RV401
RV301 RV341 RV311 RV411
IC602 CN601
LRRL
     
RV441
PB LEVEL
– DECK B –
REC BIAS
LR
  
PB LEVEL
– DECK A –
TAPE SPEED
RV1002 RV1001
(NORMAL) (HIGH)
CN1001
         

– 19 –
CD SECTION
Notes:
1. CD block basically constructed to operate without adjustment. There-
fore, check each item in order given.
2. UseYEDS-18 disc (Part No.: 3-702-101-01) unless otherwise indicated.
3. Use the oscilloscope with more than 10 MΩimpedance.
4. Clean an object lens by an applicator with neutral detergent when the
signal level is low than specified value with the following checks.
S-Curve Check
Connection:
Procedure:
1. Connect the oscilloscope to TP (FE) and TP (VC) on BD board.
2. Connect between test point TP (FOK) and GND by lead wire.
3. Turned 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. Confirm that the oscilloscope waveform (S-curve) is symmetri-
cal between A and B. And confirm peak to peak level within
3.0 ± 1.0 Vp-p.
S-curve waveform
6. After check, remove the lead wire connected in step 2.
Note: • Try to measure several times to make sure that the ratio ofA : 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
Connection:
Procedure:
1. Connect the oscilloscope to TP (RF) and TP (VC) on BD board.
2. Turned power switch on.
3. Put disc (YEDS-18) in and press the flbutton.
4. Confirm that the 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.
within 3.0 ± 1.0 Vp-p
RF signal waveform
When observing the eye pattern, set the oscilloscope forAC range
and raise vertical sensitivity.
+
–
BD board
TP (FE)
TP (VC)
oscilloscope
A
B
symmetry
+
–
BD board
TP (RF)
TP (VC)
oscilloscope
(AC range)
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
(with the 10: 1 probe
in use)
level: 1.3 Vp-p
+0.25
–0.20
E-F Balance (Traverse) check
Connection:
Procedure:
1. Short-circuit SL502 of the VIDEO board to GND.
2. Connect oscilloscope to test point TP (TE) on BD board.
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 sledding servo are turned OFF.)
6. Check the level B of the oscilloscope’s waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following:
Traverse waveform
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 6.
Traverse waveform
8. Desolder the short-land (SL502) short-circuited at step 1.
A ×100 = less than ± 22 (%)
B
level: 1.3 ± 0.6 Vp-p
+
–
BD board
TP (TE)
TP (VC)
oscilloscope
A (DC
voltage)
B
0 V
Center of the waveform
C (DC
voltage)
0 V
Tracking servo
Sled servo
OFF
Tracking servo
Sled servo
ON

– 20 –
Connection Location:
[BD Board] (Side A)
CN102
CN101
IC103
IC101
TP
(FOK)
TP
(TE)
TP
(FE)
TP (RF)
TP (VC
)