Daewoo Akf-0305 Service Manual

S/M No : AKF0305EF1

Service Manual

Car Audio Basic, RDS & OIRT Band

MODEL : AKF-0305 Series

AKF-0315 Series

4-Channel High Power (35W x 4Ch)

Electronic Tuning

Electronic Volume/Bass/Treble/Balance/Fader Controls

Auto Memory/Preset Scan

Repeat/Random/Intro Scan

Loudness Controls

Local/DX Switch

Detachable Face for Anti-Theft

DAEWOO ELECTRONICS CO., LTD

http://svc.dwe.co.kr

Mar. 2000

TABLE OF CONTENTS

1.	PRODUCT SPECIFICATIONS .........................................	1
2. LINE DRAWING ...................................................		2
3.	EMERGENCY TROUBLE SHOOT ...................................	5
4.	ADJUSTMENTS ...............................................................	9
5.	SCHEMATIC DIAGRAM ..................................................	14
6. PARTS LOCATION ON P.C.BOARD ...........................		17
7. OVERALL EXPLODED VIEW & PARTS LIST ..................		23
8. DECK MECHANISM EXPLODED VIEW & PARTS LIST ...........		25
9. PARTS LIST .......................................................................		28
10. FUNCTION OF MICOM IC ...............................................		30
11. IC BLOCK DIAGRAM ...................................................		39
12. LIQUID CRYSTAL DISPLAY .........................................		46
13. OUTPUT CONNECTION DESCRIPTIONS ..........................		48

1. PRODUCT SPECIFICATIONS

AUDIO SECTION

Maximum output power	: 35watts per channel into 4 ohms.
Load impedance	: 4 ohms
Total harmonic distortion	: Less than 10% at 12 watts
Frequency response	: 100Hz( + 3dB), 10kHz(-5 + 3dB)
Control Bass/Treble	: 10 + 3dB at 100Hz/10kHz

TAPE SECTION

Track format	: 2-track / 2-channel system
Tape speed	: 4.8cm/sec
Wow / Flutter	: 0.35%max. (WRMS)

Frequency response normal (LH)tape : 63Hz to 10kHz

TUNER SECTION

(FM) Tuning range

Usable Sensitivity(MONO)

Signal to noise ratio (at 60dBu)

(MW) Tuning range

Usable Sensitivity

(LW) Tuning range Usable Sensitivity

GENERAL

Power requirements

Current consumption

Dimension (W x H x D)

Weight(Net)

:87.5 to 108MHz

87.5 to 107.9 at U.S.A

:12dBuV(4uV / 75ohms)

:More than 50dB

:522 to 1620kHz at Europe

530 to 1710kHz at U.S.A

:30dBuV

:144 to 288kHz

:40dBuV

:DC 12.0V / Rated : 14.4V (Usable : 10.8 ~15.6V) Negative ground

:10A Maximum

:178 x 50 x 156 mm

:1.75 kg

Design and specifications are subject to changes for improvements without notice.

1

2. LINE DRAWING

2-1. AKF-0305 Front Side

BASIC

RDS

2

LINE DRAWING

2-2. AKF-0315 Front Side

BASIC

RDS

3

LINE DRAWING

2-3. REAR SIDE

BASIC MODEL

RDS MODEL

RDS+CD CHANGER MODEL

4

3. EMERGENCY TROUBLE SHOOT

3-1. General Function

Yes

No sound from

speakers

A

Yes

Different each channel have output level (Front, Rear, Left, Right)

Treble or Bass

Yes

is low unusually

Yes

L.C.D or L.E.D is not turned off.

	Output connector		Yes
	is missing
	Output connector		Yes
	is inferior goods
	No
	Power IC, Output		Yes
	Socket is inferior
	goods
	Balance of front		Yes
	and rear is in one
	side
	No
	Balance of Left,		Yes
	Right is in one
	side.
	Balance of Treble		Yes
	or Bass is in one
	side.
			Yes
	Power is not
	supplied
	No
	Output voltage of		Yes
	power IC is little.
	No
	LCD or LED is		Yes
	inferior goods.

Put exactly output connector in.

Change connector superior

Change IC, Output to superior

Re-adjust Balance		Ref.	Balance = Center
of front, rear			Front:00 / Rear:00

Re-adjust Balance		Ref.	Balance = Center
			Left:00 / Right:00
of Left, Right

Re-adjust Balance		Ref.	Balance = Center
			Treble:00 / Bass:00
of Treble or Bass

Ref. Point A

Change Regulator Ref. Regulator IC output

IC and check Voltage = V output voltage.

Change LCD or Ref. Electrical Parts List

LED to superior L.C.D., L.E.D. goods.

5

EMERGENCY TROUBLE SHOOT

3-2. Tuner Function

		Yes		No selected the		Yes		Select exactly
Hearing noise								broadcasting
				station
								frequency.
only
		A									CAT-6, 7 etc
				Tuner Module is				Change tuner		Ref.
								module to			Electrical Parts List
				inferior goods.
								superior goods.

Extreme noise in broadcast

Weak separation of FM stereo

Station in

.

Yes		Weak frequency		Change to goods of
		area caused by		R.D.S function.

B

			No
			Antenna		Yes		Put exactly
			connector is				antenna connector
			missing				in his jack
										Function of auto-
Yes			Weak frequency		Yes		Switch		Ref.
			area of FM, AM				automatically to			switch noise
							mono mode in			reduction
							weak frequency
Yes					Yes		area
			No selected the					B
			local stations.

R1	In case of located Glass Antenna, check if heat wire is cut or not in rear window.
R1	Check Antenna connector part.

6

EMERGENCY TROUBLE SHOOT

3-3. Tape Function

No sound from

Yes

Tape is inferior

Yes

Use only superior

goods

goods

speakers

A

No signal play

Yes

Put

output connector

output

in.

No

Tape Deck Macha

Deck Mechanism

Yes

Change

Ref.

ADM-21/22

is inferior goods.

superior

Yes

Tape was inserted

Yes

Insert recording

Tape is not

right side left.

part to right side.

inserted into

No

the slot.

Tape is cut or

Tape is ejected

Yes

Ref. Point A

Ref.

after being

extended

inserted.

Some program is played back repeatedly

Sound is low or not clear

Yes		Selected repeat		Yes		Release RPT		Ref.	Check on L.C.D
									and press RPT
		(RPT) function.				function
									button.
Yes		Head is dirty		Yes		Clean head or
						pinch roller with
						cleaner

7

									EMERGENCY TROUBLE SHOOT
3-4. CDC Function
	Disc is not		Yes		Discs are fold in		Yes		Put one disc in
					magazine slot.				magazine slot.
	inserted.
					No
					Magazine is not		Yes		Insert exactly
					inserted rightly				magazine

Yes

No sound

A

Selection time

Yes

is longer than unusually

Inside degree of		Yes
the unit is
extreme
No

	Indoor degree is		Yes
	so cold
	No
			Yes
	8Pin connector is
	missing
	No
			Yes
	Disc is inferior
	goods
	No
			Yes
	Disc is dirty
	No
	Selected PAUSE		Yes
	function
	No
	Selected MUTE		Yes
	function
	No
	Mechanism is		Yes
	inferior goods
	Inspect disc for		Yes
	scratches.

Turn power off and		Ref.	protective function
stop operation for			is started caused by
about 1 hour			inside degree is
			extreme.
Turn power on
and stand by for
about 1 hour

Put exactly CD-C 8Pin connector in.

Change disc to superior goods

Wipe with cleaning cloth

Release PAUSE function

Release function

Change

superior

Ref. Point A

Ref. DWEC CD-C series AKD-60, 70, 80, 100C

Ref. DWEC CD-C series AKD-60, 70, 80, 100C

8

4. ADJUSTMENTS

4-1. EQUIPMENTS CONNECTIONS

9

ADJUSTMENTS

4-2. TUNER MODULE ADJUSTMENT LOCATIONS

10

ADJUSTMENTS

4-3. AM (MW/LW) ADJUSTMENT METHOD

1.Dummy Antenna Circuit

2.Location of Adjustment Points

Refer to Adjustment Location Page

3.Control Setting

Power Switch ..................			ON	Balance/Fader Control		......................	Mech. Center
Band Switch ....................			AM	Treble/Bass Control ...........................			Mech. Center
Other		...............................	OFF
4. Adjustment Procedure
STEP		DESCRIPTION	CONNECTION	ANTENNA SIGNAL		DIAL	ADJUSTMENT
						CONTROL
				522KHz 60dBu			Adjust AM OSC
1		Band Covering	Figure 1			522KHz	for 1.2-1.35V(VT)
				Mod 1000Hz 30%
							Fig.7
				603KHz 30dBu			Adjust AM RF1 and
2		RF-Tracking	Figure 2			603KHz	AM RF2
				Mod 1000Hz 30%			for maximum output
							Fig.7
				1404KHz 30dBu			Adjust AM RF1 and
3		RF-Tracking	Figure 2			1404KHz	AM RF2
				Mod 1000Hz 30%			for maximum output
							Fig.7
4		LW Band Covering	Figure 1	144KHz 60dBu		144KHz	Adjust LW OSC
							for 1.2-1.35V(VT)
				Mod 1000Hz 30%
							Fig.7
				220KHz 60dBu			Adjust LW RF1 and
5		LW-Tracking	Figure 2			220KHz	LW RF2
				Mod 1000Hz 30%			for maximum output
							Fig.7
NOTE: When it is U.S.A band instead of 522, 603, 999, 1404kHz is 530, 600, 1000, 1400kHz

11

ADJUSTMENTS

4-4. FM ADJUSTMENT METHOD

1.Dummy Antenna Circuit

2.Location of Adjustment Points

Refer to Adjustment Location Page

3.Control Setting

Power Switch .................			ON	Balance/Fader Control		.....................	Mech. Center
Band Switch ...................			FM	Treble/Bass Control .........................			Mech. Center
Other		...............................	OFF
4. Adjustment Procedure
STEP		DESCRIPTION	CONNECTION	ANTENNA SIGNAL		DIAL	ADJUSTMENT
						CONTROL
				98.1MHz 60dBuV			Adjust FM DET
1		IF (Zero Volt)	Figure 3			98.1MHz	for 0V + 0.03V
				No Modulation
							Fig.7
		RDS Receiving		98.1MHz 42dBuV			Adjust RV 108 Page7.
							Tuner PC Board
4			Figure 4	Mod.		98.1MHz
		estimation level		1kHz 30% Mono			for2.7V=20mV at
							TP102(IC401 pin 66)
				98.1MHz 60dBuV			Adjust MPX SEP Fig.7
5			Figure 5	Mod.		98.1MHz
		Stereo Separation					for maximum separation
				1kHz 30% Stereo Left
							Left and Right ch.
				at Right ch.
				98.1MHz 35dBuV			Adjust Stereo Blend
6		SNC	Figure 5	Mod.		98.1MHz	Fig.7 1dB separation
				1kHz 30% Stereo Left			between Left and Right
				at Right ch.			ch.

12

ADJUSTMENTS

4-5. TAPE ADJUSTMENT METHOD

NOTE : 1. Clean the playback head before adjustment

2.Prepare the test tape MTT-114 or equivalent

3.Balance, Fader, Bass & Treble ....Center position. Volume adjusted to 2Volts.

	STEP	DESCRIPTION	TEST TAPE	CONNECTION	TEST	ADJUSTMENT	ADJUSTMENT
					POINT	POINT
		Head azimuth	MTT-114N		Speaker	Head azimuth	Turn the azimuth
	1			Figure 6			screw to obtain
		adjustment	or equivalent		Output	adjustment screw
							maximum level
	2	Tape Speed	MTT-114N	Figure 6	Speaker	Tape Speed	Adjust for 3010-
			or equivalent		Output	adjustment	3020Hz

Note : dBu uV dBu uV

17 5.0 33 44.6

16 6.31 35 56.2

30 31.6 45 178

NOTE : Antenna signal is used.

1.For Signal Generator with readings in EMF(Open type) add 12dB (6dB for the “Dummy” and 6dB for EMF-reading).

2.For Signal Generator with reading in dBm add 6 dB for “Dummy”

13

Size:A3

5. SCHEMATIC DIAGRAMS

5-1. BASIC Series AKF-0305 / AKF-0315

14