Onkyo DTA-94 Schematic

PC BOARD CONNECTION DIAGRAM

DTA-9.4

SURROUND BACK LEFT

XLR

INPUT

RCA

SELECT

P301

S301

P302

R430

P608B

OFFSET

U15

NAAF-7797

POWER AMPLIFIR PC BOARD

P601C

-B

BLUE

E601

P601A

P9911B

P9911A

U3

RED

DC

MODULATOR

OR

TEMPERATURE

P704

+B

OUTPUT

OPERATION

WARNING

CURRENT

P601B

P607A

INDICATOR

P702

GNDC

E

-B

+B

To NAPS-7789

AC INLET

P995

NL

AC-G

P997A

WHT

WHT

BLK

AC-H

BLK

F901

P996A

NAETC-7801

AC INLET PC BOARD

P608A

+5VC

OUTPUT

P607B

P501

WHITE

RL701

RL501

Q512

P502

BLACK

E501

HEAT SINK

P303

U16

R710

P703

JL701A

JL701B

NAAF-7798

U6

NAPS-7792

Q506 Q505 Q511

RL502

GMUTE

PHTCP

OUTRL

FMUTE

ERR

P701

SURROUND LEFT

XLR

INPUT

RCA

SELECT

P301

S301

P302

R430

P608B

OFFSET

U15

NAAF-7797

POWER AMPLIFIR PC BOARD

P601C

-B

BLUE

E601

+B

RED

P601A

DC

OUTPUT

OPERATION

MODULATOR

WARNING

INDICATOR

OR

CURRENT

TEMPERATURE

P704

P607A

+B

P601B

P702

GNDC

E

-B

P608A

+5VC

OUTPUT

P607B

P501

WHITE

RL701

RL501

Q512

P502

BLACK

E501

P303

U16

R710

JL701A

JL701B

NAAF-7798

Q506 Q505 Q511

RL502

P701

GMUTE

PHTCP

OUTRL

FMUTE

ERR

P703

XLR

P302

R430

OFFSET

U15

NAAF-7797

POWER AMPLIFIR PC BOARD

HEAT SINK

P601C

-B

BLUE

E601

+B

P601A

RED

DC

OUTPUT

OPERATION

MODULATOR

WARNING

INDICATOR

OR

CURRENT

TEMPERATURE

P704

P607A

+B

INPUT

SELECT

-B

S301

P601B

LEFT

P301

P608B

P702

RCA

GNDC

P303

P608A

ERR

+5VC

OUTPUT

P607B

P501

P502

WHITE

BLACK

E501

RL701

RL501

Q512

U16

R710

JL701B

Q506 Q505 Q511

JL701A

RL502

GMUTE

PHTCP

OUTRL

FMUTE

P701

P703

U15

NAAF-7797

HEAT SINK

P601C
BLUE

E601

RED

P601A

DC

MODULATOR

OR

TEMPERATURE

NAAF-7798

P704

E

CENTER

XLR

INPUT

RCA

SELECT

P301

S301

OFFSET

+B

P607A

P608B

P601B

P702

E

-B

P302

R430

POWER AMPLIFIR PC BOARD

-B

+B

OUTPUT

OPERATION

WARNING

INDICATOR

CURRENT

12V TRIGGER TERMINAL PC BOARD

12V TRIGGER IN

E9902

P9908A

P9910

E9903

To NAAF-7797

SURR BACK LEFT

SURR LEFT

LEFT

CENTER

RIGHT

SURR RIGHT

SURR BACK RIGHT

E

SURR BACK LEFT

SURR LEFT

LEFT

CENTER

RIGHT

To NAAF-7797

SURR RIGHT

SURR BACK RIGHT

+B

P9909

P9908B

U7

NAPS-7793

WARNING

POWERSUPPLY

CONTROL PC BOARD

D9805

F9801

P9907B

P9911C

YEL

T9801

AC-G

AC-H

P9904

JL9906A

BRN

U9

P9904A

NASW-7795

S9801

POWER

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POWER SWITCH
PC BOARD

SURR BACK LEFT

SURR LEFT

LEFT

CENTER

RIGHT

To NAAF-7797

POWER

D9812

A

P9907A

K

STAND-BY

WARNING

D9813

SURR RIGHT

SURR BACK RIGHT

-B

U8

NAETC-7794

DISPLAY LED
PC BOARD

OPERATION CHECK-4

OPERATION INDICATOR IN THE UNIT-1

DTA-9.4

(RED)

D705

DC OUTPUT

D705 (DC OUTPUT)

This LEDTurned on when DC voltage is detected between speaker output
terminals.
Spealer output relay is turned off while having detected DC voltage.
The relay will return automatically, if DC voltage output is lost.

(ORANGE)

D710

MODULATOR

OPERATION

D710 (MODULATOR)

This LED shows the state of operation of an modulation circuit.
Immediately after a power supply injection, the light is switched on, and
this LED will put out the light, if operation of modulation circuit is started.

(RED)

D751

TEMPERATURE

OR

CURRENT

P601C
BLUE

E601

P601A

-B

+B

RED

DC

OUTPUT

OPERATION

MODULATOR

OR

CURRENT

TEMPERATURE

P704

XLR

R430

WARNING

INDICATOR

U15

SELECT

OFFSET

P607A

NAAF-7797

INPUT

RCA

P601B

P702

OUTPUT

E501

RL701

RL501

Q512

L505

Q506 Q505 Q511

JL701A

RL502

P701

P703

D751 (TEMPERATURE OR CURRENT)

This LED is turned on when an unusual temperature rise and unusual
over-current of an amplifier circuit are detected.

(RED)

D9805

POWER SUPPLY

WARNING

D9805(POWER SUPPLY WARNING)

This LED is turned on when abnormalities arise in the
power supply circuit.

SUPPLY

WARNING

POWER

D9805

U7

P9908B

NAPS-7793

P9909

Q9803

Q9827

Q9806

F9801

P9907B

1A/125V

P9911C

YEL

AC-H AC-G

P9904

JL9906A

T9801

BRN

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OPERATION CHECK-5

OPERATION INDICATOR IN THE UNIT-2

DTA-9.4

U2

GND2
+12V
PROT
+12V
RL­RL+

JL9906B

P903B

(RED)

NAPS-7789

P161

PROT
TEST

E102

Q103

D161

PROT

RL+

RL-

GND2

D161

PROT

(RED)

REGULATED

This LED is turned on when the voltage of a secondary power supply output is normal.

D133

The detection circuit which is source of the drive about this LED is supervising only
the voltage difference between the positive power supply of secondary voltage, and the
negative power supply.

D133 (REGULATED)

E122 E121

E126 E125

(RED)

LOW

CURRENT

E124 E123

E101

D136

+B

E114

E

-B

E113

E174

E175

P101A

L102

E192

TH1

TH2+

TH2-

E112

E173

L101

E191

D136 (LOW CURRENT)

This LED is turned on when a low load measure circuit operates.
When the switching power supply of this unit has very little load to a power supply,
the voltage of a secondary side output rises rapidly.
In such a case, a problem is avoided by lowering voltage.

VOLTAGE

ADJUST

+B

+B

GND2

CTRL1

CTRL2

P131A

R139

REGULATED

D133

LOW

CURRENT

D136

D923

D920D921 D922

+B

-B

GND

VOLTAGE
CHECK

P108

JL132B

This circuit may operate temporarily at the time of a power supply ON.

D161 (PROT)

This LED is turned on when the protection circuit of a power supply operates.
The protection circuit of a power supply section consists of following detection circuits.

1. Over voltage detection of a secondary DC output.

2. Thermal detection of primary power supply circuit.

3. Thermal detection of secondary power supply circuit.
This LED may be turned on only for a moment. It is because the state of a protection circuit is not held in NAPS-7789.

U1

NAPS-7788

(RED)

PRI DC

LIVE

U5

NAPS-7790

PRI

E906

L103

P101B

GND

SEC

E984

L906

UDD UJJ

UJJ

UDD

E986

UDD

D102 D101D104 D103

E990

T901

UJJ

P902A

E991

E988

E987

T902

E985B

E985A

UDD

UJJ

VC+

VC-

VC-

E904

E902

E901

SEC

P997B

RL-

BLK

AC-H

P996B

AC-G

WHT

P903A

RL+

GND2

PRI

RL902

PRIDC

E905

RL902

RL901

BLK
P801A
AC-H2

E982

P801B

AC-G2

WHT

D907

LIVE

E981

E903

E983

D902

D907 (PRI DC LIVE)

D907

This LED is turned on when the electric charge remains in the primary side capacitor.
Do after discharging by resistance and checking putting out lights of this LED, when
disassembling a unit.

D851 (TH1 PROT)

This LED lights up at the time of the usual operation.
The light is put out when the thermal protection circuit of
a primary power supply section operates.

P803A

SEC

TH1

GND2

TH2-

TH2+

CTRL1+BCTRL2

+B

T854

E895

R861

Q884

R848

TH1 PROT

Q851

D851

E806

JL805B

Q882

T852

Q881

T853

Q883

R181

T851

E892

E893

E894

PRI

E891

E881

AC-H2 AC-G2

P801C

P801C

E841

(RED)

TH1 PRO

Q813

Q842

D851

Q801

Q817

Q812

Q814

P902B

E989

FORTEST

12V INPUT
+-

P904

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OPERATION CHECK-6

CAUTION IN THE CASE OF SPEAKER OUTPUT CHECK

The power amplifier circuit of DTA-9.4 is BTL system.
Therefore, in case you check speaker output, should be careful of the following point.

1. Do not connect the minus side OUTPUT terminal, and ground of the unit (Fig-1).

2. Do not connect minus of each OUTPUT terminal. (Fig-2).

3. Cannot check with an oscilloscope between the plus side of an OUTPUT terminal, and Chassis GND. (Fig-3).

Fig-1

OUTPUT

LEFT

CENTER

Oscilloscope

DTA-9.4

RIGHT

Fig-2

LEFT

CENTER

RIGHT

Fig-3

LEFT

Chassis GND of unit

OUTPUT

OUTPUT

CENTER

RIGHT

Chassis GND of unit

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OPERATION CHECK-1

CURRENT DETECTION OF POWER SUPPLY

Notes

No load and No signal input.

How to check?

1. Connect the power supply card to a wall outlet.

2. Power On the unit.

3. Short-circuit the both ends of P161 on NAPS-7789.

4. Check that it is as follows.

GND2
+12V
PROT
+12V
RL­RL+

JL9906B

P903B

DTA-9.4

P161

PROT
TEST

P161

PROT
TEST

E102

D161

PROT

RL+

RL-

GND2

Q103

U2

NAPS-7789

E122 E121

E126 E125

E124 E123

+B

E114

E

-B

E174

E175

E101

P101A

L102

E113

E192

TH2+

TH2-

E112

E173

L101

E191

+B

+B

TH1

GND2

CTRL1

CTRL2

P131A

REGULATED

D133

D136

D923

D920D921 D922

VOLTAGE

+B

-B
GND

ADJUST

VOLTAGE

CHECK

R139

P108

LOW

CURRENT

JL132B

Standby

Power

Lights

Blinks

RELAYS AND INDICATORS

How to check?

2. Connect the power supply card to a wall outlet.

4. Power On the unit.

5. Immediately after power switch On.

Check

Blinks

Power

Standby

4. About 1 second after turning On a power supply.

Check

RL501 and RL502 Relays ON.

5. About 10 seconds after turning On a power supply.

Check

RL701 Relays ON.

Check

Lights

XLR

INPUT

SELECT

P302

R430

OFFSET

U15

NAAF-7797

P601C

-B

BLUE

E601

P607A

+B

RED

P601A

DC

OUTPUT

OPERATION

MODULATOR

WARNING

INDICATOR

Q604

OR

CURRENT

TEMPERATURE

Q711

P704

Q717

RCA

P301

S301

P608B

P601B

P608A

Q603

P702

GNDC

OUTPUT

P607B

P501

P502

WHITE

P303

P504

L505

GMUTE

PHTCP

OUTRL

FMUTE

ERR

+5VC

BLACK

E501

RL701

RL501

Q512

P503

Q506 Q505 Q511

JL701A

RL502

P701

P703

RL701

RL501

RL502

Standby

Power

Blinks stop

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OPERATION CHECK-2

DC VOLTAGE DETECTION OF POWER AMPLIFIER CIRCUIT

Notes

No load and No signal input.

How to check?

1. Connect the power supply card to a wall outlet.

2. Power On the unit.

3. Set the INPUT SELECT switch of a rear panel to the RCA side.

4. Apply DC+3V to a RCA terminal.

5. Check that the speaker relay RL701 is turned off.

6. Apply DC+3V to a RCA terminal.

7. Check that the speaker relay RL701 is turned off.

Rear panel

DTA-9.4

DC+3V or -3V

OVER CURRENT DETECTION OF POWER AMPLIFIER CIRCUIT

Notes

1. Check only one channel at a time.

2. Interrupt a input signal, immediately after a speaker relay goes out.

3. Don't change into the state where load was connected to amplifier, more than for 3 seconds.

How to check?

1. Set the output of the oscillator into the minimum level.

2. Connect the oscilloscope to the OUTPUT terminal.

3. Output a 200Hz rectangular wave from an oscillator, and input into a RCA terminal through the appointed differentiation circuit.

4. Turn on the unit.

5. Adjust the output level of oscillator so that the level of the waveform of the OUTPUT terminal become 35 Vp-p.

6. Connect 2-ohms load to the OUTPUT terminal.

7. Check that the speaker relay RL701 is not turned off .

8. Connect 0.3-ohm load to the OUTPUT terminal.

9. Check that the speaker relay RL701 is turned off immediately.

Differentiation
circuit.

200Hz

35Vp-p

Input

GND

3.3k

0.1 F

10k

1SS133

3.3k

Output

0.01 F

GND

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OPERATION CHECK-3

THERMAL DETECTION OF POWER AMPLIFIER CIRCUIT

Notes

No load and No signal input.

How to check?

1. Connect the power supply card to a wall outlet.

2. Power On the unit.

3. Short-circuit the both ends of P703 on NAAF-7797.

4. Check that it is as follows.

U15

R430

OFFSET

NAAF-7797

POWER AMPLIFIER PC BOARD

DTA-9.4

Check

Light

D751

OR

TEMPERATURE

CURRENT

P601C
BLUE

E601

P601A

RED

DC

MODULATOR

TEMPERATURE

-B

P601B

P607A

+B

OUTPUT

OPERATION

WARNING

Q604

INDICATOR

OR

CURRENT

P704

Q603

Q711

Q717

P702

P703

P703

Short

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DISASSEMBLING PROCEDURES-4

DISASSEMBLING OF POWER SUPPLY UNIT

Remove 18 soldering.

13

Front side

17

DTA-7

By doing the following work, You can separate NAPS-7789
and NAPS-7790.

1. Disconnect the terminal PCB assy NAPS-7791.

2. Remove the four screws.

NAPS-7791

Remove the four screws.

14

Remove the five screws.

15

By doing the following work, You can separate NAPS-7790

18

and the heat sink.

1. Remove two soldering.

2. Remove the six screws.

By doing the following work, You can separate NAPS-7789

19

and the heat sink.

1. Remove four soldering.

2. Remove the nine screws.

By disconnect the socket assy P801, You can remove

16

the PCB assy NAPS-7788.

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DISASSEMBLING PROCEDURES-2

REMOVE A POWERB AMP. UNIT AND A POWER SUPPLY UNIT FROM CHASSIS

DTA-9.4

Remove the three screws.

1 4

Rear panel

Remove the four screws.

2

Front side

Move the power supply unit to front side.

Power supply unit

Front side

Take out a power amp. unit from the chassis.

5

Power amp. unit

Remove the eight screws.

3

Front side

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DISASSEMBLING PROCEDURES-3

REMOVE A POWERB AMP. UNIT AND A POWER SUPPLY UNIT FROM CHASSIS

DTA-9.4

Remove the four screws.

7 11

Front side

Remove the four screws.

8

12

Move the power supply unit to up side.

Power supply unit

NAPS-7788

Soldering side

Power supply unit

9

Remove the two screws.

By removing each screw of three copper plates

10

(RETAINER), You can remove an amplifier unit
completely.

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DTA-9.4

RCA

P301

P607B

P303

P608A

P702

GMUTE

PHTCP

OUTRL

FMUTE

ERR

+5VC

GNDC

GND2
+12V
PROT
+12V

RL­RL+

JL9906B

E904

E902

SEC

E901

NAPS-7790

P701

WHITE

P501

Q512

Q506 Q505 Q511

E102

OUTPUT

P502

RL501

RL502

P703

D161

BLACK

RL701

JL701A

E501

P161

PROT
TEST

Q103

PROT

U16

R710

JL701B

NAAF-7798

XLR

P302

R430

U15

NAAF-7797

HEAT SINK

POWER AMPLIFIR PC BOARD

P601C

-B

BLUE

E601

+B

RED

P601A

DC

OUTPUT

OPERATION

MODULATOR

WARNING

INDICATOR

OR

CURRENT

TEMPERATURE

P704

E122 E121

E126 E125

INPUT

SELECT

OFFSET

P607A

E

-B

+B

E124 E123

U2

RL-

P903B

RL-

GND2

AC-H

P996B

P997B

AC-G

PRI

RL+

GND2

P903A

RL+

RL902

BLK

WHT

RL902

RL901

PRI DC

D907

LIVE

E981

E903

NAPS-7789

SECONDARY POWER SUPPLY
PC BOARD

E905

BLK
P801A
AC-H2

E982

P801B

AC-G2

WHT

E983

D902

U4

NAETC-7802

E881

E891

U5

SWITCHING CONTROL PC BOARD

P801C

PRI

AC-G2

AC-H2

RIGHT

RCA

P301

S301

P608B

P601B

P702

E892

P607B

P501

WHITE

P303

P608A

GMUTE

PHTCP

OUTRL

FMUTE

ERR

+5VC

GNDC

P701

+B

E

E175

E101

E113

TEMPERATRE
SENSOR
PC BOARD

PRI

JL805B

E894

E893

T851

R181

OUTPUT

P502

RL701

RL501

Q512

Q506 Q505 Q511

RL502

P703

E114

E906

U11

BLACK

E501

JL701A

-B

P101A

L102

E192

R184

L103

E984

UDD

R854

Q881

JL805B

T852

D851

SURROUND RIGHT

XLR

INPUT

SELECT

S301

P302

R430

OFFSET

U15

NAAF-7797

HEAT SINK

U16

R710

JL701B

NAAF-7798

E174

JL132A

P101B

GND

U1

NAPS-7788

PRIMARY POWER SUPPLY
PC BOARD

UDD UJJ

UJJ

NAETC-7802

Q882

E806

Q851

TH1 PROT

POWER AMPLIFIR PC BOARD

P601C

-B

BLUE

E601

P607A

+B

RED

P601A

DC

OUTPUT

OPERATION

MODULATOR

WARNING

INDICATOR

OR

CURRENT

TEMPERATURE

P704

E

-B

+B

+B

TH1

GND2

TH2+

TH2-

CTRL1

E112

E173

L101

E191

D920D921 D922

SEC

L906

E986

UDD

UJJ

TEMPERATRE
SENSOR
PC BOARD

R848

Q884

Q883

T853

TH2+

SEC

R861

E895

+B

CTRL1+BCTRL2

GND2

TH2-

TH1

P803A

P601B

+B

CTRL2

D133

E990

P902A

RCA

P301

P608B

P702

P131A

REGULATED

T901

T854

GNDC

D923

E988

UDD

P902B

P303

P608A

FMUTE

ERR

+5VC

D136

E985A

OUTRL

CURRENT

D102 D101D104 D103

PHTCP

GMUTE

VOLTAGE

ADJUST

R139

LOW

VC-

OUTPUT

P607B

P501

P502

WHITE

BLACK

E501

RL701

RL501

Q512

U16

R710

P703

JL701A

JL701B

NAAF-7798

P701

VOLTAGE

P108

Q506 Q505 Q511

RL502

+B

-B

GND

CHECK

SURROUND BACK RIGHT

XLR

INPUT

SELECT

S301

R430

P608B

OFFSET

P302

U15

NAAF-7797

HEAT SINK

POWER AMPLIFIR PC BOARD

P601C

-B

BLUE

E601

P601A

RED

DC

MODULATOR

TEMPERATURE

+B

OUTPUT

OPERATION

WARNING

OR

CURRENT

P704

INDICATOR

+B

P607A

P601B

E

-B

RCA

P301

P702

GNDC

P608A

+5VC

OUTPUT

P607B

P501

WHITE

RL701

RL501

Q512

P502

BLACK

E501

HEAT SINK

P303

U16

R710

JL701A

JL701B

NAAF-7798

Q506 Q505 Q511

RL502

P701

GMUTE

PHTCP

OUTRL

FMUTE

ERR

P703

JL132B

P131B

E991

E989

E987

U14

NAPS-7791

T902

FORTEST

12V INPUT

+-

P904

E985B

UJJ

VC+

VC-

P803B

Q842

E841

Q801

Q817

TERMINAL PC BOARD

[NOTES]

SOCKET ASSY

JUMPER WIRE

BORAD TO BOARD

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