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— 9 —

1. Connect frequency counter to the positions shown below.
2. Tune the set to 98MHz.
3. Adjust the RV1, so that the frequency counter reading becomes

76,000Hz.

Specification Value :

Digital frequency counter
    75,950 – 76,050 Hz

0.01

µ

F

FM RF SSG

telescpic
antenna
input(ANT1)

Carrier frequency : 98MHz
IF frequency : According to
the color of CF1.
Modulation : no modulation
Output level : 0.1V (100dB)

Frequency counter

0.01

µ

F

+
–

33k 

Ω

IC1 Pin 

4

IC1 Pin 

7

BLACK

10.64MHz

BLUE

10.67MHz

RED

10.70MHz

ORANGE

10.73MHz

WHITE

10.76MHz

color
mark

CF1

Adjustment Location : MAIN board (Component side)

CF1

T2

L2

L4

L3

T1

RV1

IC701

CT1 (1/4)

CT1 (2/4)

L1

L2

FM Tracking
Adjustment

CT1 (3/4)

L3

AM Tracking
Adjustment

FM Frequency Coverage
Adjustment

CT1 (4/4)

L4

ANT 1

AM Frequency Coverage
Adjustment

T2 : AM IF Adjustment

RV1 : FM VCO

Adjustment

T1 : FM IF

Adjustment

IC1 : VCO
Frequency counter

IC1

15

11

16

18

1

30

4

— 10 —

1.

Perform the traverse check in the CD test mode.
After check, be sure to exit the test mode.

2.

Perform check in the order given.

3.

Use the disc (YEDS-18, Parts No. 3-702-101-01) only when
so indicated.

Put the set into test mode and perform the following  checks.
Repair if there are any problems.

• Sled Motor Check
Press 

+ , = keys and confirm that the Optical pick-up  moves

smoothly from the innermost to outermost circumference and back
smoothly and with no catching or abnormal noises.
(Cancellation of BTL mute)
+ : Optical pick-up moves to the outer circumference.
= : Optical pick-up moves to the inner circumference.

1.

Press the CD 

^ key. (Focus search operation is performed

continuously.)

2.

Look at the Optical pick-up objective lens and confirm that it
moves up and down smoothly, with no catching or abnormal
noises.

3.

Press 

p button.

Confirm that focus search operation stops. If it does not, press
p button again longer.

1.

Disconnect the AC power cord.

2.

Short-circuit the lands as shown on the CONTROL (1) board.

3.

Connect the AC power. (LCD 501 indicator blinks the test mode
pattern.)

Turn off the POWER.

[CONTROL (1) BOARD] – CONDUCTOR SIDE –

Adjustment Location : MAIN board

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

Check Procedure:
1.

Connect the oscilloscope to test point TP (VC) and TP (TE) on
MAIN board.

2.

Put the set into test mode.

3.

Optical pick-up setting to the center by 

+ or = button

pushing.

4.

Insert disk (YEDS-18) and press 

^ button.

5.

Check that the oscilloscope traverse waveform is symmetrical,
as shown in the figure below.

6.

Release test mode after adjustment is completed.

[MAIN BOARD] – CONDUCTOR SIDE –

A

B

C

0V

VOLT/DIV : 0.1V
TIME/DIV  : 1ms

A = B     C = 500mV 

±

 100mV

Jumper wire

Test portion

Short : Test mode
Open : Normal mode

TP(FE)

TP(RF)

TP(TE)

TP(TE)

TP(VC)

TP(VC)

Osilloscope
(DC range)

+

–

— 11 —

Adjustment Location : MAIN board (Component side)

This check is to be done when the optical block replaced.

Check Procedure:
1. Connect the oscilloscope to test point TP (VC) and TP (RF) on

MAIN board.

2. Put the set into test mode.
3. Opitical pick-up setting to the center by + or – button pushing.
4. Insert disk (YEDS-18) and press 

^ button.

5. Press the MODE button. (Tracking servo ON)
6. Check that the oscilloscope wavewform is as shown in the figure

below (eye pattern).
A good eye pattern means that the diamond shape (

◊

) in the

center of the waveform can be clearly distinguished.

7. Release test mode after adjustment is completed.

• RF signal reference waveform (eye pattern)

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

[MAIN BOARD] – CONDUCTOR SIDE –

Adjustment Location : MAIN board (Component side)

(See page 12)

A frequency response analyzer is necessary in order to perform this
check exactly.
However, this gain has a margin, so even if it is slightly off, there is
no problem.
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.

Tracking

Gain

Symptoms

Focus

•  The time until music starts

becomes longer for STOP ➡
CD 

^ or automatic

selection (

0 , ) buttons

pressed). (Normally takes
about 2 seconds.)

•  Music does not start and disc

continues to rotate for STOP
➡ CD ^ or automatic
selection (

0 , ) buttons

pressed.)

•  Sound is interrupted during

PLAY. Or time counter
display stops progressing.

•  More noise during 2-axis

device operation.

low

—

—

high

low or high

low

low

high

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

1.2 

±

 0.2Vp-p

Check Procedure:
1. Keep the set horizontal.
2. Inset disk (YEDS-18) and press 

^ button.

3. Connect an oscilloscope to TP (FE) and TP (VC) on the MAIN

board.

4. Check that the waveform is as shown in the figure below. (Focus

waveform)

TP(FE)

TP(RF)

TP(RF)

TP(TE)

TP(VC)

TP(VC)

Osilloscope
(DC range)

+

–

— 12 —

•

Good Example

•

Incorrent Examples (DC level changes more than on adjusted
waveform)

5.

Connect an oscilloscope between TP (TE) and TP (VC).

6.

Insert disc (YEDS-18) and press the CD 

^ button.

7.

Check that the waveform is as shown in the figure below.
(tracking waveform)

low focus gain

high focus gain

low tracking gain

high tracking gain
(high fundamental wave than for low gain)

100mV

0V

VOLT/DIV : 100mV
TIME/DIV : 1ms

VOLT/DIV : 100mV
TIME/DIV : 2ms

200mV

0V

VOLT/DIV : 100mV
TIME/DIV : 2ms

75mV

0V

VOLT/DIV : 1V
TIME/DIV : 2ms

0V

VOLT/DIV : 1V
TIME/DIV : 2ms

0V

VOLT/DIV : 1V
TIME/DIV : 2ms

0V

TP(FE)

TP(RF)

TP(TE)

TP(TE)

TP(FE)

TP(VC)

TP(VC)

Osilloscope
(DC range)

+

–

•

Incorrect Examples (Fundamental wave appears)