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– 17 –

•

µ

Pin No.

Pin Name

I/O

Function

1

ILLIN

I

Dimmer detection signal input terminal    Dimmer is present at input of “L” (fixed at “L”)

2

POS3

I

3

POS2

I

4

POS0

I

5

POS1

I

6

TAPEON

O

Tape system power supply on/off control signal output terminal    “H”: tape on

7

CM ON

O

Capstan/reel motor (M901) drive signal output terminal    “H”: motor on

8

LM LOD

O

Loading/tape operation motor control signal output to the MM1322XFBE (IC351)
(For the loading direction and forward side operation)    *1

9

LM EJ

O

Loading/tape operation motor control signal output to the MM1322XFBE (IC351)
(For the eject direction and reverse side operation)    *1

10

TUNON

O

Tuner system power supply on/off control signal output to the BA3918 (IC611)    “H”: tuner on

11

FM ON

O

FM system power supply on/off control signal output to the BA3918 (IC611)    “H”: FM on

12

PW ON

O

Main system power supply on/off control signal output to the BA3918 (IC611)    “H”: power on

13

MUT

O

Line muting control signal output terminal    “H”: line muting on

14

VOLCE

O

Chip enable signal output to the electrical volume  (IC331)

15

VOLCKO

O

Serial data transfer clock signal output to the electrical volume  (IC331)

16

VOLSO

O

Serial data output to the electrical volume  (IC331)

17

AMPON

O

Standby control signal output to the power amplifier  (IC751)    “L”: standby

18

AMPMUT

O

Muting control signal output to the power amplifier  (IC751)    “L”: muting on

19

DX/LO

O

Local/DX selection signal output to the FM/AM tuner unit (TU1)    “L”: DX, “H”: local

20

AM MONO

O

AM forced monaural signal output terminal    Not used (open)

21

GND

—

Ground terminal

22

DSTSEL

I

Destination setting terminal (Fixed at “L” in this set)

23

DBASIN

I

D-BASS switch (SW951) input (A/D input)

24

KEYIN1

I

Key input terminal (A/D input)    LSW921 to LSW927
(

6, INTRO 1, REPEAT 2, 3, BL. SKIP 6, ATA 5, 4 keys input)

25

KEYIN0

I

Key input terminal (A/D input)    LSW901 to LSW909, 911, 912, 930
(OFF, SOURCE, MODE 

*, + + ) SEEK AMS, = 0 – SEEK AMS, VOLUME –,

SEL, VOLUME +, MUTE , BTM, LCL, DSPL keys input)

26

RC IN0

I

Rotary remote commander shift key A/D input terminal

27

VSM

I

FM and AM signal meter voltage detection input from the FM/AM tuner unit (TU1)

28

AMIFIN

I

AM intermediate frequency detection signal input from the FM/AM tuner unit (TU1)

29

FMIFIN

I

FM intermediate frequency detection signal input from the FM/AM tuner unit (TU1)

30

VDD2

—

Power supply terminal (+5V)

31

FM OSC

I

FM local oscillator detection signal input from the FM/AM tuner unit (TU1)

32

AM OSC

I

AM local oscillator detection signal input from the FM/AM tuner unit (TU1)

33

GND

—

Ground terminal

34

NCO

O

Not used (open)

35

EO1

O

Main charge-pump control signal output terminal

36

TEST0

I

Setting terminal for the test (fixed at “L”)

37

AM STIN

I

Not used (open)

38

SEKOUT

O

Seek control signal output to the FM/AM tuner unit (TU1)

39

MW/SW

O

MW/SW selection signal output to the FM/AM tuner unit (TU1)    “L”: MW, “H”: SW

40

BEEP

O

Beep sound output terminal

41

KEYACK

I

Input of acknowledge signal for the key entry    Acknowledge signal is input to accept function
and eject keys in the power off status    On at input of “H”

Tape position detect input from tape operation switch on the mechanism block

– 18 –

Pin No.

Pin Name

I/O

Function

42

BU IN

I

Battery detect signal input terminal    “H”: battery on

43

MTLSEL

I/O

44

DOLON

I/O

45

AMSIN

I

Whether a music is present or not from CXA2509AQ (IC301) is detected at auto music sensor
“L”: music is present, “H”: music is not present

46

ST

I/O

47

AMS ON

O

Tape auto music sensor control signal output to the CXA2509AQ (IC301)
“L” is output to lower the gain for audio level at FF/REW

48

N/R OUT

O

Forward/reverse direction control signal output to the CXA2509AQ (IC301)
“L: forward direction, “H”: reverse direction

49

TAPMUT

O

Tape muting on/off control signal output to the CXA2509AQ (IC301)    “H”: tape muting on

50

ILLON

O

51

SD IN

I

Station detector detect input from the FM/AM tuner unit (TU1)
Stop level for SEEK, BTM, etc. is determined    SD is present at input of “H”

52

NOSESW

I

Detects the removal of the attaching and removing type front panel block    “L”: attaching

53

TELMUT

I

Telephone muting signal input terminal    At input of “L”, the signal is attenuated by –20 dB

54

REL T

I

Reel table rotation detect signal input from the take-up and supply reel sensor

55

ACCIN

I

Accessory detect signal input terminal    “L”: accessory on

56

TESTIN

I

Setting terminal for the test mode    “L”: test mode (normally fixed at “H”)

57

RC IN1

I

Rotary remote commander shift key A/D input terminal

58

PW SEL

I

Power select switch (S501) input terminal
“L”: position A (halt mode), “H”: position B (operation mode)

59

MTLIN

I

Input terminal to set whether the auto metal function is present or not
“L”: auto metal function is present (fixed at “H”)

60

ADON

O

Power supply on/off control signal output for the A/D conversion

61

KEYSEL

I

Setting terminal for the key (fixed at “H”)

62

SEKOUTSEL

I

Active selection terminal for the SEKOUT (pin #•) (fixed at “L”)

63

COLORSEL

I

Setting terminal for the illumination color    “L”: amber, “H”: green (fixed at “H”)

64

LCDCE

O

Chip enable output to the liquid crystal display driver (IC901)

65

LCDCKO

O

Serial data transfer clock signal output to the liquid crystal display driver (IC901)

66

LCDSO

O

Serial data output to the liquid crystal display driver (IC901)

67

LCDINH

O

Blank indicate control signal output to the liquid crystal display driver (IC901)
“L”: no display

68

UNICKI

I

Serial data reading clock signal input terminal    Not used

69

UNISO

O

Serial data output terminal    Not used (open)

70

UNISI

I

Serial data input terminal    Not used (fixed at “L”)

71

UNICKO

O

Serial data transfer clock signal output terminal    Not used (open)

Input of FM stereo detection signal from FM/AM tuner unit (TU1), and output of forced
monaural control signal to FM/AM tuner unit (TU1)  (Commonly used for stereo display input
and forced monaural output)
FM stereo detection at input of “L”, forced monaural at output of “L”

Dolby control in/out terminal
At initial mode: valid/invalid selection input of dolby function (“L” input: valid)
At normal mode: dolby on/off control signal output (“H” output : dolby on)
Not used this function in this set (fixed at “H”)

METAL control in/out terminal
At initial mode: auto/manual mode selection input of METAL function    “L”: manual mode
At manual mode: METAL on/off control signal output terminal (“H” output: METAL on)
At auto mode: input at MTLIN (pin %ª)
Not used this function in this set (fixed at “H”)

Power supply on/off control signal output terminal at the illumination and liquid crystal display
driver (IC901)    “H”: power on
At power select switch (S501) on mode: “H” output at the accessory on
At power select switch (S501) off mode: “H” output at the power on

– 19 –

Pin No.

Pin Name

I/O

Function

72

BUSON

O

Bus on/off control signal output terminal    “L”: bus on    Not used (pull up)

73

SYSRST

O

Reset signal output terminal    “L”: reset    Not used (pull up)

74

VREG

O

CPU regulator output terminal    Connected to capacitor

75

GND

—

Ground terminal

76

X OUT

O

Main system clock output terminal (4.5 MHz)

77

X IN

I

Main system clock input terminal (4.5 MHz)

78

CE

I

CPU chip enable signal input (fixed at “H”)

79

VDD1

—

Power supply terminal (+5V)

80

RESET

I

System reset signal input from the reset signal generator (IC551) and reset switch (S551)
“L”: reset    “L” is input for several 100 msec after power on, then it changes to “H”

*1  loading/tape operation motor control

                          MODE

 TERMINAL

LM LOD (pin 8)

“H”

“L”

“H”

“L”

LM EJ (pin 9)

“H”

“H”

“L”

“L”

STOP

LOADING/

FORWARD

EJECT/

REVERSE

BRAKE

– 20 –

Note on Schematic Diagram:
• 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

specified.

•

¢

: internal component.

•

C

: panel designation.

•

U

: B+ Line.

• Power voltage is dc 14.4V and fed with regulated dc power

supply from ACC and BATT cords.

• Voltages and waveforms are dc with respect to ground

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

) : AM (MW)

〈〈

 

〉〉

: TAPE PLAYBACK

∗

: Impossible to measure

• 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

f

: AM (MW)

E

: TAPE PLAYBACK

• X

: parts extracted from the component side.

•

¢

: internal component.

• b

: Pattern from the side which enables seeing.

(The other layers' patterns are not indicated.)

Caution:
Pattern face side:

Parts on the pattern face side seen from

(Conductor Side)

the pattern face are indicated.

Parts face side:

Parts on the parts face side seen from

(Component Side) the parts face are indicated.