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– 17 –

• The time until music starts becomes longer

for 

π

 

m fl on automatic selection.

low

low or high

(

≠

, 

±

 buttons pressed.)

(Normally, takes about 2 seconds.)

• Music does not start and disc continues

to rotate for 

π

 

m fl or automatic

–

low

selection.

(

≠

, 

±

 buttons pressed.)

• Sound is interrupted during PLAY. Or

–

low

time counter display stops progressing.

• More noise during 2-axis device

high

high

operation.

This adjustment is to be done when the optical pick-up block is
replaced.

1. Connect the oscilloscope between TP (RF) and TP (VC).
2. Insert disc (YEDS-18) and push the 

fl button.

3. Adjust RV701 so that the oscilloscope waveform is maximum as

shown in the figure below (eye pattern).

• RF signal reference waveform (eye pattern)

A frequency response analyzer is necessary in order to perform this
adjustment exactly.
However, this gain has a margin, so even if it is slightly off, there is
no problem. Therefore, do not perform this adjustment.
Focus/tracking gain determines the pick-up follow-up (vertical and
horizontal) relative to mechanical noise and mechanical shock when
the 2-axis device operate.
However, as these reciprocate, the adjustment is at the point where
both are satisfied.
• When gain raised, the noise when the 2-axis device operates

increases.

• When gain is lowered, it is more susceptible to machanical shock

and skipping occurs more easily.

When gain adjustment is off, the symptoms below appear.

When observing the eye pattern, set the oscilloscope for AC range
and raise vertical sensitivity.

 

See page 19.

oscilloscope
(DC range)

CD board

TP (RF)
TP (VC)

0V

1.1 – 1.5 V

VOLT / DIV : 0.2 V
TIME / DIV : 500 nS

– 18 –

The following is a simple adjustment method.

Since exact adjustment cannot be performed, remember the
positions of the controls before performing the adjustment.
If the positions after the simple adjustment are only a little
different, return the controls to the original position.

1. Keep the set horizontal.

If the set not horizontal, this adjustment cannot be performed due
to the gravity against the 2-axis device.

2. Insert disc (YEDS-18) and push the 

fl button.

3. Connect the oscilloscope between TP  (FE) and TP (VC).
4. Adjustment RV704 so that the waveform is as shown in the

figure below. (focus gain adjustment)

• Correct Example

5. Connect the osilloscope between TP (TE) and TP (VC).
6. Adjust RV703 so that the waveform is as shown in the figure

below. (tracking gain adjustment)

• Correct Example

• Incorrect Examples (DC level changes more than on adjusted
  waveform)

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

100 mV

0 V

250 mV

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

75 mV

100 mV

• Incorrect Examples (fundamental wave appears)

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

0 V

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

Adjustment Location : See page 19.

low focus gain

high focus gain

low tracking gain

high tracking gain

(higher fundamental wave than for low gain)

oscilloscope
(DC range)

CD board

TP (FE)

TP (TE)
TP (VC)

– 19 –

RV702

TRAVERSE

Adjustment

TP (RF)

TP (VC)

TP (FE)

TP (TE)

IC701

CNP701

R714

RV703

TRACKING GAIN

Adjustment

RV701

FOCUS BIAS

Adjustment

RV704

FOCUS GAIN

Adjustment

Adjustment Location: CD board

–CD board (conductor side)–

– 20 –

Pin No.

Pin Name

I/O

Pin Description

1 – 19

SEG0 – 18

O

LCD drive segment output

20 – 23

COM0 – 3

O

LCD drive common output

24 – 26

VLC-3 – 1

O

LCD drive voltage terminal

27

VL

O

LCD drive port ON/OFF output

28

RMC

I

Sircs receiver input

29

C-SCOR

I

CD SCOR input

30

TX

O

Oscillation output (32.768 kHz)

31

TXE

I

Oscillation input (32.768 kHz)

32

RST

I

System reset input

33

N.C.

—

Not used.

34

VDD

—

Power supply pin (+5 V)

35 – 38

KEY1 – 4

I

Key input

39

INIT

O

Tuner select initial setting output

40

VER

I

Tuner destination band select input

41

9K/10K

I

Tuner band 9k/10k select input

42

REG-CHK

I

Voltage detection input

43

N.C.

—

Not used.

44

C-SQCK

O

CD Sub-Q read clock output

45

C-SENS

I

CD SENSE input

46

C-SQSO

I

CD Sub-Q data input

47

A-MUTE

O

Audio mute output

48

V-DATA

O

Volume serial data output

49

V-CLK

O

Volume serial clock output

50

V-CE

O

Volume serial chip enable output

51

REG-CON

O

Regulator control output

52

TAPE

O

Tape control output

53

RADIO

O

Radio control output

54

CD

O

CD control output

55

REC

I

Tape record signal input

56

CD-DOOR

I

CD door detection input

57

R-COUNT

I

Tuner PLL data input

58

R-ST

O

Stereo indicator output

59

C-MUTE

O

CD mute output

60

PA-CON

O

Power-amplifier control output

61

WP

I

Wake-up input

62

T-PLAY

I

Tape play switch input

63

C-XRST

O

CD reset output

64

C-DATA

O

CD serial data output

65

C-CLK

O

CD serial clock output

66

C-XLAT

O

CD serial latch output

67

R-MUTE

O

Tuner mute output

68

R-DATA

O

Tuner PLL data output

69

R-CLK

O

Tuner PLL clock output

70

R-CE

O

Tuner PLL chip enable output

71

VSS

—

GND

72

XTAL

O

Oscillation output (4.19 MHz)

73

N.C.

—

Not used.

74

EXTAL

I

Oscillation input (4.19 MHz)