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6

NOTE : The preset data will be erased when this test mode is used. Therefore, take down the data before setting this mode and preset the data

again after completing operations in this mode.

1-1. Display Tube Check

1-1-1. Turn OFF the power.
1-1-2. While pressing 1 and  BAND  together, turn ON  POWER .
1-1-3. While continuously pressing 1 and  BAND  together, check the following.

(1) All light up

1-2. Key Check

1-2-1. Release 1 and  BAND . The KEY CHECK mode will be set.
1-2-2. All key numbers will be displayed.

Key Number : 23

1-2-3. Each time the key is pressed, the key number will be counted down.

Each key will be counted only once, at the first time.

1-2-4. When all keys have been pressed, the process will end and the factory preset will be entered.

To skip “1. Display Tube Key Check Mode”, and factory preset :

(1) Turn OFF the power.
(2) While pressing 3 and  BAND  together, turn ON  POWER .

Set to the reception frequency that the circuit can receive (FM : STEREO, RDS stations). (Set the input level to above 70 dB.)
This enables circuit check to be performed in any of the reception modes-FM, AM (MW, LW). Set to a desired band before setting the test
mode.

(1) Turn OFF the power.
(2) While pressing 4 and  BAND  together, turn ON  POWER .

•  The items in the following table will be checked automatically in order every 2 seconds.

(2) 8-digit test pattern

(3) 2-digit test pattern

The display changes every 500 msec.

Microcomputer version indication (1 sec) 

t All light up (1) t 8-digit test pattern (2) t 2-digit test pattern (3)

T

FM RDS

Display

Items

TUNED

IF

SIG L

ST

RDS

AST signal = LOW

IF COUNT OK

SI LEVEL    70dB

ST signal = LOW

RDS DATA OK

DISPLAY

OK or NG

OK or NG

OK or NG

OK or NG

OK or NG

AM (MW, LW)

OK or NG

NG

IC201 NG, RV201 adjustments

TB101, IC201 NG

TB101 NG

TB101 NG

IC801 NG

=

>

7

Clears all the RAMs and sets the initial state.

(1) Turn OFF the power.
(2) While pressing 5 and  BAND  together, turn ON  POWER .

1. Turn OFF the power.
2. While pressing 2 , turn ON  POWER .

•  A step of AM channels can be changed over between 9 kHz and 10 kHz.
1. Turn OFF the power.
2. While pressing 9 or -, turn ON  POWER .

8

Procedure:
1. Tune the set to 98 MHz.
2. Push the  DISPLAY  button for digital signal meter indication.
3. Adjust RV201 to the place where level and “70dB”  indication

lights on fluorescent indicator tube.

FM RF signal
generator

set

FM ANTENNA
75 

Ω

 coaxial

(TB101)

Carrier frequency  : 98 MHz
Modulation

: 1 kHz, 40 kHz deviation

Output level

: 6.3 mV (76dB

µ

)

(75 

Ω

 open)

IC201

CN101

RV201

FM SIGNAL LEVEL

Adjustment

9

9

Note on Printed Wiring Board:
•

X

: parts extracted from the component side.

•

: Pattern from the side which enables seeing.

• Indication of transistor.

B

These are omitted.

C

E

Q

Note on Schematic Diagram:
• All capacitors are in 

µ

F unless otherwise noted.  pF: 

µµ

F

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

specified.

•

f

: internal component.

•

2

: nonflammable resistor.

•

C

: panel designation.

•

U

: B+ Line.

•

V

: B– Line.

•

H

: adjustment for repair.

• Voltages and waveforms are dc with respect to ground

under no-signal (detuned) conditions.
no mark : FM

∗

: Can not be measured.

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

Ω

).

Voltage variations may be noted due to normal produc-
tion tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal produc-
tion tolerances.

• Circled numbers refer to waveforms.

• Signal path.

F

: FM

Note: The components identified by mark 

0

 or dotted line

with mark 

0

 are critical for safety.

Replace only with part number specified.

1

IC701 

eg

 (X2)

2

IC801 

qf

 (OSCO) (AEP, UK model only)