DOWNLOAD Sony HCD-GRX5 / HCD-RX66 / MHC-GRX5 / MHC-RX66 Service Manual ↓ Size: 6.57 MB | Pages: 70 in PDF or view online for FREE

– 13 –

0 dB=0.775 V

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

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

  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback

set

main board
CN301
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

main board
CN301
Pin 

2

 (GND)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

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 sup-

ply voltage unless otherwise noted.

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

Mode

FWD

Torque meter

CQ-102C

Meter reading

FWD
back tension

REV

REV
back tension

FF/REW

FWD tension

REV tension

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

– 14 –

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.

3. Mode:  Playback

4. After the adjustments, apply suitable locking compound to

the pats adjusted.

Adjustment Location: Playback Head (Deck A).

 Record/Playback/Erase Head (Deck B).

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

MAIN
board
CN301
set

test tape
P-4-A100
(10 kHz, –10 dB)

pin 

1

oscilloscope

L-CH

R-CH

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

pin 

2

pin 

3

L

R

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

p

button, 

[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

u

button.

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

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

forward

reverse

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

main board
CN301 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

frequency counter

+
–

set

test tape
P-4-L300
(315 Hz, 0 dB)

main board
CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

– 15 –

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

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

CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

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

[MAIN  BOARD] (Component Side)

[AUDIO  BOARD]  (Component Side)

[LEAF  SW  BOARD]  (Component Side)

+
–

set

recorded
portion

CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

set

MD/VIDEO (AUDIO) IN
315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

REC LEVEL

1

3

RV301

L

RV351

R

CN106

CN301

CN107

















RV401

RV301

RV341

RV311

RV411

IC602

CN601

L

R

R L





 





 

RV441

PB LEVEL

– DECK B –

REC BIAS

L

R





 

PB LEVEL

– DECK A –

TAPE SPEED

RV1002

RV1001

(NORMAL)  (HIGH)

CN1001





















r

INTRODUCTION
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 au-
tomatically switch to VIDEO.
(If do not operation of stopped from recording complete, and press

– 

0 button then rewind to recording start position.)

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

P button, then recording

start.

r

INTRODUCTION
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 au-
tomatically switch to VIDEO.
(If do not operation of stopped from recording complete, and press

– 

0 button then rewind to recording start position.)

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

P button, then recording

start.

– 16 –

1. CD Block is basically designed to operate without adjustment.  There-

fore, 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 10 M

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.

Procedure:
1. Connect oscilloscope to test point TP (FEO).
2. Connect between test point TP (FOK) and GND 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±1
Vp-p.

S-curve waveform

6. After check, remove the lead wire connected in step 2.

• 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.

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.

Clear RF signal waveform means that the shape “≈” can be clearly
distinguished at the center of the waveform.

+
–

BD board

TP (FEO)
TP (VC)

oscilloscope

A

B

symmetry

within 3 

±

 1 Vp-p

+
–

BD board

TP (RF)
TP (VC)

oscilloscope

VOLT/DIV: 200 mV
TIME/DIV: 500 ns

level:
1.3 

±

 0.3 Vp-p

Procedure:
1. Connect oscilloscope to test point TP (TEO) on BD board.
2. Turned Power switch on. Press 

[FUNCTION]

 button to select

CD.

3. Put disc (YEDS-18) in to play the number five track.
4. Press the

p

button, 

[ENTER/NEXT]

 button and 

^ but-

ton simultaneously several times to fluorescent indicator tube
display “SHUFFLE” is blink. (The sledding servo is turned
OFF.)

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:

Traverse waveform

6. Press the

p

button, 

[ENTER/NEXT]

 button and

^ button

simultaneously several times to fluorescent indicator tube dis-
play “SHUFFLE” is OFF. (The sleding servo is turned ON.)
Confirm the C (DC voltage) is almost equal to the A (DC volt-
age) is step 5.

Traverse waveform

+
–

BD board

TP (TEO)
TP (VC)

oscilloscope

A (DC 

voltage)

B

0 V

level: 500 

±

 100 mVp-p

symmetry

Center of the waveform

C (DC 

voltage)

0 V

Sled servo ON

Sled servo OFF

A

×

 100 = less than ±7 (%)

B