HCD-XB8, LBT-XB8AV, MDS-B5 - Sony Audio Service Manual (repair manual). Page 12

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4. After the adjustments, apply suitable locking compound to the

parts adjusted.

Adjustment Location: Playback Head (Deck A)

Record/Playback/Erase Head (Deck B)

4 5 ˚

9 0 ˚

135˚

180˚

wrong

good

in phase

Waveform of oscilloscope

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 1 dB of peak.

3. Mode: Playback

set

test tape
P-4-A100
(10kHz, –10dB)

main board
CN403
Pin 

3

 (L-CH)

oscilloscope

Pin 

2

 (GND)

L

Pin 

1

 (R-CH)

Note: Set the test mode using the following method and begin tape

speed adjustment.
In the test mode, the tape will move at double speed while
the  H SPEED DUB.  button is pressed.

Procedure :
With the power turned ON, press the  SPECTRUM ANALYZER
button,  ENTER  button, and  EFFECT  button simultaneously.
(The “VOLUME” on the fluorescent display tube will blink while
in the test mode.)
To exit the test mode, press the  POWER  button.

1. Load WS-48B into deck A and a recordable tape into deck B.
2. Press the  

r REC  button, and press the  ·  button of deck B to

set deck B into the recording state.

3. Play deck A.
4. While pressing the  H SPEED DUB.  button, set double speed

play.

5. Adjust RV652 of the AUDIO board so that the reading of the

frequency counter becomes 6000 ± 30 Hz.

6. Release the  H SPEED DUB.  button to set normal speed play.
7. Adjust RV651 of the AUDIO board so that the reading of the

frequency counter becomes 3000 ± 15 Hz.

Adjustment Location: AUDIO board

Procedure:
Mode: Playback

output
level

L-CH
peak

screw
position

R-CH
peak

within
1dB

within 1dB

L-CH
peak

R-CH
peak

screw
position

R

reverse

forward

set

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

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301
(L-CH) and RV401 (R-CH)
so that adjustment within the following adjustment level.

Adjustment level:
CN403 playback 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