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– 25 –

3. Adjust the volume RV2 on TU1 by turning clockwise untill

“0” is shown next to “FM” on the display window, If “0” is
already shown or the volume RV2 has been turned too far,
turn it back counterclockwise untill “0” is disappeared once,
then try this adjustment.

Display

Adjustment Location: See page 28.

This set have the test mode function. In the test mode, FM Auto
Scan/Stop Level and MW Auto Scan/Stop Level adjustments can
be performed easier than it in ordinary procedure.

<Set the Test Mode>
1. Set the “power select” switch (SW500) is “A (ON)” position.
2. Turn ON the regulated power supply. (All LEDs on the set

lights up, and the clock is displayed.)

 Press the

[OFF]

button, if the clock is not displayed.

3. Push the preset 

[4]

 button.

4. Push the preset

[5]

button.

5. Press the preset

[1]

button for more than two seconds.

6. Then the display indicates all lights, the test mode is set.

<Release the Test mode>
1. Push the 

[OFF]

 button.

2. Return the “power select” switch (SW500) to initially set po-

sition.

MD section adjustments are done automatically in this set.

See the adjustment location from on page 28 for the ad-
justment.

 0 dB=1µV

When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.

 Adjust the tuner section in the sequence shown below.

1. FM Auto Scan/Stop Level Adjustment
2. FM Stereo Separation Adjustment (Wide)
3. FM Stereo Separation Adjustment (Narrow)
4. FM RDS S-Meter Adjustment
5. MW Auto Scan/Stop Level Adjustment

[SOURCE]

 button : FM

Procedure:
1. Set to the test mode.
2. Push the 

[SOURCE]

 button and set to FM.

Display

set

antenna jack (CN1)

FM RF signal

generator

Carrier frequency

: 98.00 MHz

Output level

: 22 dB (12.6 

µ

V)

Mode

: mono

Modulation

: 1 kHz, 22.5 kHz deviation (30%)

0.01 

µ

F

SHUF

REG

SHUF

REG

– 26 –

[SOURCE]

 button : FM

Procedure:
1. Adjust the volume RV3 on FM/AM tuner unit (TU1) for the

best separation.

L-CH Stereo separation: A-B
R-CH Stereo separation: C-D
The separations of both channels should be equal.

Specification: Separation more than 24 dB

Adjustment Location: See page 28.

FM Stereo

Level meter

Level meter

signal generator

connection

reading (dB)

output channel

L-CH

L-CH

A

B

L-CH

R-CH

Adjust RV3 on TU1

for minimum reading.

R-CH

R-CH

C

R-CH

L-CH

D

FM RF signal

generator

Carrier frequency : 98.00 MHz
Output level

: 70 dB (3.2 mV)

Mode

: stereo

Modulation

: main : 1 kHz, 33.75 kHz deviation (45%)
  sub : 1 kHz, 33.75 kHz deviation (45%)

:

 19 kHz pilot: 7.5 kHz deviation (10%)

0.01 

µ

F

set

antenna jack (CN1)

+
–

level meter

10 k

 

Ω

REAR
AUDIO OUT

(75 

Ω)

[SOURCE]

 button : FM

Procedure:
1. Push the 

[SHIFT]

 button.

2. Push the 

[4]

 button four times.

3. Push the 

[5]

 button twice and set to narrow mode.

4. Adjust the volume RV4 on FM/AM tuner unit (TU1) for the

best separation.

L-CH Stereo separation: A-B
R-CH Stereo separation: C-D
The separations of both channels should be equal.

Specification: Separation more than 18 dB

Adjustment Location: See page 28.

FM RF signal

generator

Carrier frequency : 98.00MHz
Output level

: 70 dB (3.2 mV)

Mode

: stereo

Modulation

: main : 1 kHz, 20 kHz deviation (26.5%)
  sub : 1 kHz, 20 kHz deviation (26.5%)

:

 19 kHz pilot: 7.5 kHz deviation (10%)

0.01 

µ

F

set

antenna jack (CN1)

+
–

level meter

10 k

 

Ω

REAR
AUDIO OUT

(75 

Ω)

FM Stereo

Level meter

Level meter

signal generator

connection

reading (dB)

output channel

L-CH

L-CH

A

B

L-CH

R-CH

Adjust RV4 on TU1

for minimum reading.

R-CH

R-CH

C

R-CH

L-CH

D

– 27 –

[SOURCE]

 

n 

[MODE]

 button : MW

Procedure:
1. Set to the test mode. (See page 25.)
2. Push the 

[SOURCE]

 button and set to FM.

3. Push the 

[MODE]

 button and set to MW.

Display

4. Adjust the volume RV1 on TU1 by turning clockwise untill

“0” is shown next to “MW” on the display window, If “0” is
already shown or the volume RV1 has been turned too far,
turn it back counterclockwise untill “0” is disappeared once,
then try this adjustment.

Display

Adjustment Location: See page 28.

[SOURCE]

 button : FM

Procedure:
1. Set to the test mode. (See page 25.)
2. Push the 

[SOURCE]

 button and set to FM.

Display

3. Push the preset 

[10]

 button .

4. Adjust RV1 on MAIN board so that the display indication is

“13.0”.

Display

Specification: Display indication: 12.8 to 13.2.

Adjustment Location: See page 28.

set

antenna jack (CN1)

FM RF signal

generator

Carrier frequency

: 98.00 MHz

Output level

: 35 dB (56.2 

µ

V)

Mode

: mono

Modulation

: no modulation

0.01 

µ

F

SHUF

REG

SHUF

REG

AM RF signal

generator

Carrier frequency : 999 kHz
30% amplitude
modulation by
1 kHz signal
Output level

: 33 dB (44.7 

µ

V)

(50 

Ω

)

set

AM dummy antenna

30 

Ω

15 pF

65 pF

antenna jack (CN1)

TP

SHUF

TP

SHUF

– 28 –

TU1

RV1 MW Auto Scan/Stop Level Adjustment

RV2 FM Auto Scan/Stop Level Adjustment

RV3 FM Stereo Separation Adjustment (Wide)

RV4 FM Stereo Separation Adjustment (Narrow)

RV1 FM RDS S-Meter Adjustment

Front