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— 13 —

15

7

4

1

30

16

IC1

CV1

CF1

L1
FM Tracking
Adjustment

L2
FM Frequency
Coverage
Adjustment

T2
AM IF
Adjustment

L4
AM Frequency
Coverage
Adjustment

RV1
FM VCO
Adjustment

L3
AM Tracking
Adjustment

FM ANT IN

T1
FM IF
Adjustment

AM OSC

AM OSC

FM OSC

FM OSC

CT4
AM Frequency
Coverage
Adjustment

CT3
AM Tracking
Adjustment

CT1
FM Tracking
Adjustment

CT2
FM Frequency
Coverage
Adjustment

Set the CT2 (FM OSC) and CT4 (AM OSC)
trimmers to their extreme outside.

Inside NG

Outside OK

Adjustment Location : MAIN board (Component side)

Adjustment Location : MAIN board (Conductor side)

— 14 —

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.

Set the function switch to power off.

2.

Set the function switch to CD while 

= key and p key

pressing.
The set is into CD test mode (

88 is displayed).

3.

Turn the power off to release test mode.

Turn the POWER OFF.

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 = 300mV – 700mV

+
–

Oscilloscope

(DC range)

TP (VC)

TP (TE)

TP (FE)

— 15 —

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 16)

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

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)

VOLT/DIV : 0.2V
TIME/DIV : 500ns

0.9Vp-p – 1.3Vp-p

+
–

Oscilloscope

(DC range)

TP

(RF)

TP(VC)

— 16 —

•

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)

[MAIN BOARD] (Conductor side)

•

Incorrect Examples (Fundamental wave appears)

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 : 0.2V
TIME/DIV : 2ms

0V

VOLT/DIV : 0.2V
TIME/DIV : 2ms

0V

VOLT/DIV : 0.2V
TIME/DIV : 2ms

0V

+
–

Oscilloscope

(DC range)

TP (VC)

TP (TE)

TP (FE)