Daewoo AKD-0275 Series User manual

Service Manual
Car Audio Basic, RDS
S/M No:AKD0275EF0
MODEL : AKD-0275 Series
AKD-0285 Series
DAEWOO ELECTRONICS CO., LTD
http://svc.dwe.co.kr Jan. 2000
4-Channel High Power (35W x 4Ch)
Electronic Tuning
Electronic
Volume/Bass/Treble/Balance/Fader Controls
Auto Memory/Preset Scan
Repeat/Random/Intro Scan
Local/DX Switch
Loudness & Mute Controls
Flip-Down Detachable Face for Anti-Theft
ISO DIN Chassis for Easy Installation

TABLE OF CONTENTS
1. PRODUCT SPECIFICATIONS ....................................1
2. LINE DRAWING ...............................................2
3. ADJUSTMENTS ...............................................5
4. SCHEMATIC DIAGRAM ....................................9
5. PARTS LOCATION ON P.C. BOARD ...........................12
6. OVERALL EXPLODED VIEW & PARTS LIST ...................19
7. DECK MECHANISM EXPLODED VIEW & PARTS LIST .........21
8. PARTS LIST ............................................25
9. FUNCTION OF MICOM IC ....................................28
10. IC BLOCK DIAGRAM ....................................33
11. LIQUID CRYSTAL DISPLAY ...................................38
12. OUTPUT CONNECTION DESCRIPTIONS ......................40
13. HOW TO INSTALL ...................................41

- 1 -
1. PRODUCT SPECIFICATIONS
1-1. TECHNICAL SPECIFICATION
Power requirements : DC 12.0V / Rated : 14.4V
(Usable : 10.8 15.6V)
Negative ground
Current consumption : 10A Maximum
Dimension (W xH xD) : Body 178 x50 x165 mm
: Escutcheon 188 x58 x15 mm
Weight (Net) : 2.7 kg
Design and specifications are subject to change for improvements without notice.
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)
TUNER SECTION
(FM) Tuning range : 87.5 to 108MHz
87.5 to 107.9 at U.S.A
Usable Sensitivity(MONO) : 10dBu(4uV/75ohms)
Stereo Separation : 30dB
Channel Step : 200KHz
Signal to noise ratio (at 60dBu) : More than 50dB
(MW) Tuning range : 522 to 1620kHz at Europe
530 to 1710kHz at U.S.A
Usable Sensitivity : 28dBu
(LW) Tuning range : 144 to 288kHz
Usable Sensitivity : 40dBu
CD SECTION
DISC : Compact disc(12cm standard disc)
Revolution : 1.2m/S 1.4m/S(500rpm 200rpm)
Error correction system : CIRC
Sampling : 44.1kHz
Quantization bits : 16bit LINEAR
Frequency response : 20Hz 20kHz 3 dB
Total harmonic distortion : Less than 0.15% at 2watts
Dynamic Range : 85 dB
S/N ratio : 70 dB
Channel separation : 60 dB
1-2. GENERAL SPECIFICATION

2. LINE DRAWING
WITHOUT RDS FUNCTION : BASIC
WITH RDS FUNCTION : RDS
2-1. AKD-0275 FRONT SIDE
- 2 -

LINE DRAWING
2-2. AKD-0285 FRONT SIDE
- 3 -
WITHOUT RDS FUNCTION : BASIC
WITH RDS FUNCTION : RDS

LINE DRAWING
- 4 -
2-3. AKD-0275/AKD-0285 REAR SIDE

3. ADJUSTMENTS
- 5 -
3-1. CONNECTIONS EQUIPMENTS

ADJUSTMENTS
3-2. ADJUSTMENT LOCATIONS IN TUNER MODULES
- 6 -

ADJUSTMENTS
3-3. AM (MW/LW) ADJUSTMENT
- 7 -
STEP
1 Band Covering
RF-Tracking
Figure 1
Figure 2
Figure 2
Figure 1
Figure 2
522KHz 60dBu
Mod 1000Hz 30%
603KHz 30dBu
Mod 1000Hz 30%
1404KHz 30dBu
Mod 1000Hz 30%
144KHz 60dBu
Mod 1000Hz 30%
220KHz 60dBu
Mod 1000Hz 30%
522KHz
603KHz
1404KHz
144KHz
220KHz
Adjust AM OSC
for 1.2-1.35V(VT)
Fig.8
Adjust AM RF1 and
AM RF2
for maximum output
Fig.8
Adjust AM RF1 and
AM RF2
for maximum output
Fig.8
Adjust LW OSC
for 1.2-1.35V(VT)
Fig.8
Adjust LW RF1 and
LW RF2
for maximum output
Fig.8
RF-Tracking
LW Band Covering
LW-Tracking
2
3
4
5
DESCRIPTION CONNECTION ANTENNA SIGNAL
DIAL
CONTROL ADJUSTMENT
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
NOTE: When it is U.S.A band instead of 522, 603, 999, 1404kHz is 530, 600, 1000, 1400kHz

ADJUSTMENTS
3-4. FM ADJUSTMENT
- 8 -
STEP
1 IF (Zero Volt)
RDS Receiving
estimation level
Figure 3
Figure 4
Figure 5
Figure 5
98.1MHz 60dBuV
No Modulation
98.1MHz 45dBuV
Mod.
1kHz 30% Mono
98.1MHz 60dBuV
Mod.
1kHz 30% Stereo Left
at Right ch.
98.1MHz 35dBuV
Mod.
1kHz 30% Stereo Left
at Right ch.
98.1MHz
98.1MHz
98.1MHz
98.1MHz
Adjust FM DET
for 0V 0.03V
Fig.8
Adjust RV 101 Tuner PC
Board for2.7V=20mV at
TP102(IC401 pin 66)
Adjust MPX SEP
Fig.8
for maximum separation
Left and Right ch.
Adjust Stereo Blend
Fig.8 1dB separation
between Left and Right
ch.
Stereo Separation
SNC
4
5
6
DESCRIPTION CONNECTION ANTENNA SIGNAL
DIAL
CONTROL
ADJUSTMENT
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

4. SCHEMATIC DIAGRAM
4-1. BASIC Series AKD-0275/0285
- 9 -
Size:A3

SCHEMATIC DIAGRAM
- 10 -
4-2. RDS Series AKD-0275/0285
Size:A3

SCHEMATIC DIAGRAM
- 11 -
4-3. CDP Circuit for AKD-0275/0285 (DCM-200/201)
Size:A3

5. PARTS LOCATION ON P.C. BOARD
5-1. PCB MAIN : AKD-0275/0285
PARTS SIDE
- 12 -

PARTS LOCATION ON P.C. BOARD
- 13 -
BOTTOM SIDE

PARTS SIDE
BOTTOM SIDE
PARTS LOCATION ON P.C. BOARD
AKD-0275 BASIC
- 14 -
5-2. PCB FRONT

PARTS SIDE
BOTTOM SIDE
PARTS LOCATION ON P.C. BOARD
AKD-0275 RDS
- 15 -

PARTS LOCATION ON P.C. BOARD
- 16 -
AKD-0285 BASIC
PARTS SIDE
BOTTOM SIDE

PARTS LOCATION ON P.C. BOARD
- 17 -
AKD-0285 RDS
PARTS SIDE
BOTTOM SIDE

PARTS LOCATION ON P.C. BOARD
- 18 -
5-3. PCB Sub
PARTS SIDE
BOTTOM SIDE