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– 9 –

AM IF ADJUSTMENT

Adjust for a maximum reading on level meter

T1

455 kHz

AM (MW) FREQUENCY COVERAGE ADJUSTMENT

(Except CD820L: FR)

Adjust for a maximum reading on level meter

L4

530 kHz [526.5 kHz]

CT4

1,605 kHz [1,606.5 kHz]

AM (MW) TRACKING ADJUSTMENT

(Except CD820L: FR)

Adjust for a maximum reading on level meter

L1 (CD820)

600 kHz [598.5 kHz]

L1-1 (CD820L: AEP, UK)

CT3

1,400 kHz [1,399.5 kHz]

LW FREQUENCY COVERAGE ADJUSTMENT

(CD820L: FR)

Adjust for a maximum reading on level meter

L4

160 kHz

CT4

240 kHz

LW TRACKING ADJUSTMENT

(CD820L: FR)

Adjust for a maximum reading on level meter

L1-1

160 kHz

CT3

240 kHz

LW FREQUENCY COVERAGE ADJUSTMENT

(CD820L: AEP, UK)

Adjust for a maximum reading on level meter

CT6

145 kHz

LW TRACKING ADJUSTMENT

(CD820L:AEP, UK)

Adjust for a maximum reading on level meter

L1-2

160 kHz

CT5

240 kHz

• Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.

FM FREQUENCY COVERAGE ADJUSTMENT

Adjust for a maximum reading on level meter

L3

87.5 MHz

CT2

108.0 MHz

FM TRACKING ADJUSTMENT

Adjust for a maximum reading on level meter

L2

87.5 MHz

CT1

108.0 MHz

• Adjustment should be performed in the order given.

Setting:
Function switch: RADIO
BAND switch : FM

Setting:
Function switch: RADIO
BAND switch : MW/LW

AM RF SSG

30% amplitude modulation by 
400 Hz signal.
Output level: as low as possible

Put the lead-wire
antenna close to 
the set.

FM RF SSG

22.5 kHz frequency deviation 
by 400 Hz signal.
Output level: as low as possible

0.01 

µ

F

FM lead wire antenna terminal

level meter

set

speaker terminal

4 

Ω

+
–

0 dB=1 µV

[   ] : Italian model
• Abbreviation

FR : French model

– 10 –

1. Connect the frequency counter to 4 and 7 pins of IC1 as

shown the figure right.

2. Tune the set to 98 MHz.
3. Adjust RV1 for 76 kHz 

±

 500 Hz reading on frequency counter.

FM RF SSG

Carrier frequency: 98 MHz
Modulation: no modulation
Output level: 0.032 V (90 dB)

0.01 

µ

F

FM lead wire antenna terminal

’

‘

IC1 Pin 

4

+
–

frequency counter

33 k 

Ω

MAIN Board

IC1 Pin 

7

T1
AM IF Adjustment

RV1
FM Stereo Adjustment (76 kHz)

L1-2 (CD820L: AEP, UK)
LW Tracking Adjustment

L2

CT1

FM Tracking
Adjustment

CT3

L1
L1-1

(Except CD820L: FR):
AM (MW) Tracking 
Adjustment
(CD820L: FR):
LW Tracking Adjustment

CT5 (CD820L: AEP, UK)
LW Tracking Adjustment

L4

CT4

(CD820L: AEP, UK):
AM (MW) Frequncy Coverage Adjustment
(CD820L: FR):
LW Frequency Coverage Adjustment

CT6 (CD820L: AEP, UK)
LW Frequency Coverage Adjustment

L3 (Italian)

L3 (Except Italian)

FM Frequency Coverage 
Adjustment

[MAIN Board] (Component Side)

CT2

– 11 –

Note:
Tracking Balance Adjustment and Tracking Gain Adjustment are
done automatically in this set.

1. Set the open switch (S420) to the CLOSE position.
2. Under POWER OFF condition (when the clock appear in the

display), short the TEST terminal.

 If the power is supplied to the microprocessor once, it is backed up

for 3 minutes, and therefore the TEST mode will not be activated
within 3 minutes even if the power is turned on again. In this case,
short instantaneously the test point RST and GND.

3. Press the CD 

^ key, and the focus search is repeated.

At this time, check that the optical pickup objective lens moves
smoothly without a sticking or noise.

4. Load the test disc (YEDS-18,Part No. 3-702-101-01), and per-

form automatic adjustment after the focus search succeded.

5. After automatic adjustment is finished, move the sled motor

to the center. At this time, keep pressing the 

+ and =

keys to confirm that optical pickup moves smoothly via most
inside track 

→

 most outside track 

→

 most inside track with-

out a sticking or noise.

6. Confirm the traverse waveform.
7. Press the WAKE UP TRACK key.
8. The tracking servo and the sled servo are turned on, the mute

is cancelled, the test pattern display on, LCD disappears, and
normal CD mode becomes active.

9. Adjust the RF and jitter waveforms.

LCD Display

Connecting points: MAIN Board (See page 13)

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

Adjustment Procedure:
1. Connect the oscilloscope to test point TP (VREF) and TP (RF)

on MAIN board.

2. Insert the disc (YEDS-18, Part No.3-702-101-01) and press

CD 

^ key to play.

3. Move the optical pick-up to the music area on the disc to en-

able easy visibility of the eye pattern by 

+ and = button

pressing.

4. Adjust RV501 so that the oscilloscope waveform is as shown

in the figure below (eye pattern).
A god eye pattern means that the diamond shape (≈) in the
center of the waveform can be clearly distinguished.

• RF signal reference waveform (eye pattern)

Adjustment Location: MAIN Board (See page 13)

MAIN board

TP (RF)

TP (VREF)

+
–

oscilloscope

(AC range)

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

1.3 

±

 0.5 Vp-p

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

CD

TRACK

49

Tracking 
Gain

Tracking 
Balance

– 12 –

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 gain determines the pick-up follow-up (vertical and hori-
zontal) 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 is raised, the noise when the 2-axis device operates

increases.

• When gain is lowered, mechanical shock and skipping occurs

more easily.

• When gain adjustment is off, the symptoms below appear.

The following is a simple adjustment method.

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

• The time until music starts becomes longer for

STOP 

→

 PLAY or automatic selection.

(

=, + buttons pressed.)

(Normally takes about 2 seconds.)

• Music does not start and disc continues to

rotate for STOP 

→

 PLAY or automatic

selection.
(

=, + buttons pressed.)

• Sound is interrupted during PLAY.

Or time counter display stops progressing.

• More noise during 2-axis device operation

Gain

Focus

Symptoms

low

–

–

high

Procedure:
1. Keep the set horizontal.

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

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

^ button.

3. Connect the oscilloscope TP (FE) and TP (VREF) on MAIN

board.

4. Adjustment RV502 on MAIN board so that the waveform is

as shown in the figure below.

• Incorrect Examples (DC level changes more than on adjusted

waveform)

MAIN board

TP (FE)

TP (VREF)

+
–

oscilloscope

)

(

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

100 mV

0 V

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

200 mV

0 V

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

75 mV

0 V

low focus gain

high focus gain