DK-A1H (serv.man7) - Sharp Audio Service Manual (repair manual)

DK-A1H/DK-A1H(BK)

 – 1

®

No. S3713DKA1H///

• In the interests of user-safety the set should be restored to

its original condition and only parts identical to those speci-

fied be used.

iPod is a registered trademark of 
Apple Computer, Inc.

CHAPTER 1. GENERAL DESCRIPTION
[1]  Important Service Notes (for U.K. only) ....... 1-1
[2] Specifications .............................................. 1-1
[3] Name 

Of 

Parts ............................................ 1-3

CHAPTER 2. ADJUSTMENTS
[1] Key 

Test ...................................................... 2-1

[2] Tuner 

Test ................................................... 2-1

[3] Test 

Function ............................................... 2-2

[4]  Test Mode Initial Display ............................. 2-2
[5] User 

Reset .................................................. 2-2

[6]  All Clear (Reset).......................................... 2-2

CHAPTER 3. MECHANICAL DESCRIPTION
[1] Disassembly ................................................ 3-1

CHAPTER 4. DIAGRAMS
[1] Block 

Diagram............................................. 4-1

CHAPTER 5. CIRCUIT DESCRIPTION
[1] Voltage ........................................................5-1

CHAPTER 6. CIRCUIT SCHEMATICS AND PARTS
LAYOUT
[1]  Notes On Schematic Diagram.....................6-1
[2]  Types Of Transistor And LED .....................6-1
[3]  Chart Of Connecting Wires .........................6-2
[4] Schematic 

Diagram.....................................6-4

[5]  Wiring Side Of PWB....................................6-14

CHAPTER 7. OTHERS
[1]  Function Table Of IC ...................................7-1
[2] FL 

DISPLAY ................................................7-6

[3]  Wiring Of Primary Supply Leads

(for U.K. only)..............................................7-7

Parts marked with "      " are important for maintaining the safety of the set. Be sure to replace these parts with
specified ones for maintaining the safety and performance of the set.

®

• Note for users in U.K.

Recording and playback of any material may require

consent which SHARP is unable to give. Please refer

particularly to the provisions of Copyright Act 1956, the

Performers Protection Acts 1963 and 1972 and subsequent

statutory enactments and orders.

DK-A1H/DK-A1H(BK)

 – 2

 

Example:

Indicates lead-free solder of tin, silver and copper.

Lead-free wire solder for servicing

PWB-A

92LPWB6686MANS

92LPWB6686DPLS

PWB-C

MAIN

PWB-B

92LPWB6686PODS

iPOD

MICOM (C1) / CONTROL (C2) / KEY (C3) / AUDIO PRO (C4) / 

RE-FLASH MICOM (C5) / SUB (C6) / LED L-CH (C7) / LED R-CH (C8)

"MAIN, iPOD, MICOM, CONTROL, KEY, AUDIO PRO, RE-FLASH MICOM, SUB, LED L-CH, LED R-CH PWB" of 
this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWB and 
service manuals.The alphabetical character following LF shows the type  of lead-free solder.

When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional 
lead wire solder may cause damage or accident due to cracks.
As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40 C, we recommend 
you to use a dedicated soldering bit, if you are nto familiar with how to obtain lead-free wire solder or soldering 
bit, contact our service station or service branch in your area.

As the melting point of lead-free solder (Sn-Ag-Cu) is about 220 C which is higher than the conventional lead 
solder by 40 C,and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the 
PWB for extended period of time. However, since the land may be peeled of for the maximum heat-resistance 
temperature of parts may be exceeded, remove the bit from the PWB as soon as you confirm the steady 
soldering condition.
Lead-free solder contains more tin, and the end of the soldering bit may be easily corrected. Make sure to turn 
on and off the power of the bit as required. If a different type of solder stays on the tip of the soldering bit, it is 
alloyed with lead-free solder. Clean the bit after every use of it.
When the tip of the soldering bit is blackened during use, file it with steel wool or fine sand paper.
Be careful when replacing parts with polarity indication on the PWB silk.

i

DK-A1H/DK-A1H(BK)

1 – 3

Before returning the unit to the customer after completion of a repair or adjustment it is necessary for the following withstand voltage test to be
applied to ensure the unit is safe for the customer to use.

Setting of Withstanding Voltage Tester and set.

Set name

set value

Withstanding Voltage Tester
Test voltage

4,240 VPEAK
3,000 VRMS

Set time

6 secs

Set current (Cutoff current)

4 mA

Unit
Judgment
OK: The “GOOD” lamp lights.
NG: The “NG” lamp lights and the buzzer sounds.

PROBE

AC

OUT

UNIT

SHORT-CIRCUIT
AC POWER
SUPPLY CORD

CONNECT THE PROBE
TO VIDEO JACK

WITHSTANDING

VOLTAGE TESTER

FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER TO THE OPERATION MANUAL.

 

AC 220 - 240 V, 50 Hz

Power consumption Power on: 28 W

Power stand-by: 0.6 W (*)

PMPO: 64 W
Front Speaker:
MPO: 10 W (5 W + 5 W) (DIN 45 324)
RMS: 4 W (2 W + 2 W) (DIN 45 324)
RMS: 4 W (2 W + 2 W) (DIN 45 500)

Subwoofer:
MPO: 12 W (6 W + 6 W) (DIN 45 324)
RMS: 10 W (5 W + 5 W) (DIN 45 324)
RMS: 6 W (3 W + 3 W) (DIN 45 500)

1-way type light-up speaker system
Front Speakers: 6.5 cm (2-1/2") - 12 ohms - 
Full Range
Subwoofer: 10 cm (4") - 8 ohms - Woofer

Front Speakers: 4W/Channel
Subwoofer: 10W/Channel

Front Speakers: 2W/Channel
Subwoofer: 5W/Channel

Headphones: 16 - 50 ohms 
(recommended: 32 ohms)
Video output: 1Vp-p

Auxiliary (audio signal): 
500 mV/47 k ohms 

Width: 400 mm (15-3/4") 
Height: 145 mm (5-3/4") 
Depth: 251 mm (9-7/8")

4.3 kg (9.5 lbs.)

FM: 87.5 - 108 MHz
AM: 522 - 1620 kHz

AC 220 - 240 V, 50 Hz

Power consumption Power on: 28 W

Power stand-by: 0.6 W (*)

Front Speaker:
RMS: 4 W (2 W + 2 W) (10% T.H.D.)
RMS: 4 W (2 W + 2 W) (0.9% T.H.D.)

Subwoofer:
RMS: 10 W (5 W + 5 W) (10% T.H.D.)
RMS: 6 W (3 W + 3 W) (0.9% T.H.D.)

1-way type light-up speaker system
Front Speakers: 6.5 cm (2-1/2") - 12 ohms - 
Full Range
Subwoofer: 10 cm (4") - 8 ohms - Woofer

Front Speakers: 4W/Channel
Subwoofer: 10W/Channel

Front Speakers: 2W/Channel
Subwoofer: 5W/Channel

Headphones: 16 - 50 ohms 
(recommended: 32 ohms)
Video output: 1Vp-p

Auxiliary (audio signal): 
500 mV/47 k ohms 

Width: 400 mm (15-3/4") 
Height: 145 mm (5-3/4") 
Depth: 251 mm (9-7/8")

4.3 kg (9.5 lbs.)

FM: 87.5 - 108 MHz
AM: 522 - 1,620 kHz

*This power consumption value is obtained when the demonstration
mode is cancelled in the power stand-by mode.

*This power consumption value is obtained when the demonstration
mode is cancelled in the power stand-by mode.

1 – 1

DK-A1H/DK-A1H(BK)

1 – 4

  1. iPod Dock

 2. ON/STAND-BY Button

  3. Clock Button

  4. iPod Button

 5. Alarm Indicator

 6. Auxiliary Button

  7. Snooze/Dimmer Button

 8. Tuner Button

  9. Remote Sensor

10. Alarm Button

11. Alarm ON/OFF Button

12. E Sound Button/Demo Button

13. Play/Pause Button

14. Skip Down, Tuner Preset Down Button

15. Skip Up, Tuner Preset Up Button

16. EQ Button

17. Volume Down Button

18. Volume Up Button

1. Alarm Indicator

2. Sleep Indicator

3. iPod Indicator

4. Aux Indicator

5. FM Stereo Mode Indicator

6. FM Stereo Receiving Indicator

7. RDS Indicator

8. Summer Time Indicator 

1. AM Loop Aerial Terminal

2. AM Aerial Earth Terminal

3. FM 75 Ohms Aerial Socket

4. Auxiliary Input Sockets

5. Headphone Socket

6. Video Out Socket

7. Summer Time Switch

8. AC Input

1 – 2