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— 5 —

If the front end unit fails, it is difficult to repair the inner circuits, so
replace the entire front end unit.

Set “IF : WIDE” after the all adjustments.

•

Standard Setting of FM Stereo RF Signal Generator.

Method 1:
1. Set the reception mode to FM.
2. Push the  MENU  button and turn the  TUNING/SELECT  to

indicate “Reception” on the fluorecent display tube, then press
the  ENTER  button.

3. Rotate the  TUNING/SELECT  knob in the clokwise direction.

(Proceeds onto the step 5 when rotated in the counterclokwise
direction.)

4. Turn the  TUNING/SELECT  knob to indicate “ANT ATT :

OFF” on the fluorescent display tube, then press the  ENTER

l

button.

5. Turn the  TUNING/SELECT  knob to indicate “IF : NARROW”

or “IF : WIDE” on the fluorescent display tube, then press the

l

ENTER  button.

When the IF BAND : NARROW is set, “NARROW” is
indicated on the fluorescent display tube.

6. Set WIDE after the operation.

* When set to standby for inputs using the  TUNING/SELECT

l

knob, “SELECT” is indicated on the fluorecent display tube.

Method 2:
After the test modes “2. Display Tube Check and KEY Check mode”
or “3. Entering the Factory Preset”, “IF : NARROW” and “IF :
WIDE” are switched every time pressing RETURN button the IF
BAND : NARROW is set “NARROW” is indicated on the
fluorescent display tube.
Likewise, the mode can be switched between “ANT ATT : ON”
and “ANT ATT : OFF”. When set to ANT ATT : ON, the fluorescent
display tube indicates ANT ATT.

set

FM RF SSG

1kHz
highpass
filter

distortion meter

FM ANTENNA (75

Ω

)

LINE OUT

STEREO STANDARD SIGNAL

MONAURAL

STANDARD SIGNAL

Carrier frequency : 98MHz
Modulation : Audio 1kHz
    Main channel (L+R) : 33.75kHz

deviation

    Sub channel (L–R)

: 33.75kHz

deviation

    Pilot

: 7.5kHz

Deviation

Carrier frequency : 98MHz
Modulation : Audio 1kHz

75kHz deviation

Setting:
IF BAND : WIDE
ANT ATT : OFF

Procedure:
1. Tune the set to 98 MHz.
2. Adjust IFT252 for 0V reading on the digital voltmeter.

................... NULL

3. Adjust IFT253 for a minimum reading on the distortion meter.

................... MONO Distortion (THD)

4. Repeat the adjustments of 2 and 3 several times.

Note :

 When replacing the ceramic filter, perform this alignment.

set

FM RF SSG

1kHz
highpass
filter

distortion meter

FM ANTENNA (75

Ω

)

Modulation : Monaural Standard signal
Output level : 6mV (76dB) (at 75 

Ω

 open)

LINE OUT

Digital Voltmeter
(DC range)

TP251
NULL terminal

— 6 —

Setting:
IF BAND : WIDE
ANT ATT : OFF

Procedure:
1. Tune the set to 98 MHz.
2. Adjust RV251 to the point (moment) when the “STEREO”

indicator will change from going off to going on.

Setting:
IF BAND : NARROW
ANT ATT : OFF

Procedure:
1. Tune the set to 98 MHz.
2. Set “IF BAND : NARROW” according to the procedure of

“How to switch IF BAND WIDE/NARROW” on page 6.

3. Adjust RV231 to the point (moment) when the “STEREO”

indicator will change from going off to going on.

Setting:
IF BAND : WIDE
ANT ATT : OFF

Procedure:
1. Tune the set to 98 MHz.
2. Press  DISPLAY  button to display the digital signal, then adjust

RV221 to be display as “SIG 70dB”.

set

FM RF SSG

FM ANTENNA (75

Ω

)

Modulation : Stereo Standard signal
Output level : 18

µ

V (25dB) (at 75 

Ω

 open)

set

FM RF SSG

FM ANTENNA (75

Ω

)

Modulation : Stereo Standard signal
Output level : 18

µ

V (25dB) (at 75 

Ω

 open)

set

FM RF SSG

FM ANTENNA (75

Ω

)

Modulation : Stereo Standard signal
Output level : 3mV (76dB) (at 75 

Ω

 open)

Setting:
IF BAND : WIDE

Procedure:
1. Refer to “How to switch IF BAND WIDE/NARROW” on page

6.

L-CH Stereo separation : 

A – B

R-CH Stereo separation : 

C – D

The separations of both channels should be equal.

set

FM RF SSG

FM ANTENNA (75

Ω

)

LINE OUT

level meter

Modulation : Stereo Standard signal
Output level : 6mV (76dB) (at 75 

Ω

 open)

FM stereo

Signal generator

Output channel

L-CH

R-CH

R-CH

L-CH

Level meter

connection

L-CH

L-CH

R-CH

R-CH

Level meter

reading (dB)

A
B

Adjust RV301 for minimum
reading on Level meter

C
D

Adjust RV301 for minimum
reading on Level meter

— 7 —

Setting:
BAND : LW

Procedure:
1. Set AM RF signal generator so that the AM antenna input level

becomes 74dBµ/m.

2. Adjust RV402 so that 1 to 10 indication bars light up on the

signal meter.

[TUNER BOARD] — Component Side —

AM RF  SSG

loop antenna

set

loop antenna
(Supplied accessories)

60 cm

AM antenna
terminal (TM1)

30% amplitude
modulation by
400 Hz signal

Carrier frequency : 216kHz
Modulation : AUDIO 400Hz, 30% modulation

Field strength dB (

µ

V/m) =SSG output level dB (

µ

V/m) –26 dB.

FE101

RV402

AM Meter Level

RV251

Stereo Level

RV221

FM Meter Level

RV231
Narrow Gain

IFT252
(NULL)

TP251 (NULL)

RV301

Stereo

Separation

IFT253

(THD)

IFT252, 253

FM Discriminator

CNP702

1

8

— 8 —

•

U

: B+ Line.

•

V

: B– Line.

• Voltages and waveforms are dc with respect to ground under

no-signal (detuned) conditions.
no mark : FM
(          ) : MW
<        > : LW

∗

: Impossible to measure

• Voltages are taken with a VOM (Input impedance 10 M

Ω

).

Voltage variations may be noted due to normal production tol-
erances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal production tol-
erances.

• Circled numbers refer to waveforms.
• Signal path.

F

: FM

f

: AM

• X

: parts extracted from the component side.

• b

: Pattern from the side which enables seeing.

Note:
The components identified by mark 

!

 or dotted line with

mark 

!

 are critical for safety.

Replace only with part number specified.

C

These are omitted

E

B

IC701 

!¡

  X2

2

5.2 Vp-p

4.19MHz

4.332MHz

IC801 

!£

  OSC1

1

3.6 Vp-p

Note:
• All capacitors are in µF unless otherwise noted.  pF: µµF 50 WV

or less are not indicated except for electrolytics and tantalums.

• All resistors are in 

Ω

 and 

1

/

4

 

W or less unless otherwise speci-

fied.

•

¢

: internal component.

•

C

: panel designation

POWER SW board

TRANS board

TUNER board

DISPLAY board

ENCODER board