Genius SP-HF1255A User manual

Service Guide SP-HF1255A
1
SERVICE GUIDE
KEY SYSTEM CORP

Service Guide SP-HF1255A
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Revision History
Version Date Change
1.0 2009-12-22

Service Guide SP-HF1255A
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Table of Contents
Revision History………………………………………………………………….2
Table of contents……………………………………………………………....…3
Getting Start…………………………………………………….………………..4
Conventions Used in this Guide…………………………………………….…...4
Safety Precautions………………………………………………………….……4
Chapter 1. How to Handle Defective Returns………………………………..….5
1.2 Problem………………………………………………………………………6
1.2.1 No power，LED （indicator）unlighted………………………………...7
1.2.2 No sound…………………………………………………………….…….8
1.2.3 Right or left channel no sound….……….……….……….……..….…...…9
1.2.4 Noise………………………………….…………………………....…..…10
1.2.5 LED indicators no light…………………………….….……………...….11
1.2.6 Headphone jack output no sound……………………………..……...…..12
1.2.7 VR, headphone jack or line-in jack abnormal……..………….…...……..13
Chapter 2. Specification……………………………………………….….……14
Satellite……………………………………………………..…………….……14
Chapter 3. Block diagram…………………………………………..……...…..15
Chapter 4. Part list…………………………………… …………….………….16
Chapter 5 Important notes……………………………………………………...17
Chapter 6. Exploded view………………………………………………...……18
Right Satellite…………………………………………………..…….…...……18
Left Satellite…………………………………………………………………….19
Chapter 7 Schematic diagram……………………………………..…….………20

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Getting Started
Conventions Used in the Guide
Pay Special Attention: Instructions that are important to remember and may prevent mistakes.
Caution: Information that, if not followed, may result in damage to the product.
Safety Precautions
The following precautions should be observed in handing the speaker described in this guide:
Place the speakers on a flat, level and stable surface.
Do not place the speakers in environments subject to mist, smoke, vibration, excessive dust, salty or
greasy air, or other corrosive gases and fumes.
Do not drop or jolt the speakers.
Do not allow anything to drop into the subwoofer case through its ventilator, as it could result in
fatal electric shock or fire.
Place the unit far enough from other equipments for good heat dissipation.
Do not perform any maintenance with wet hand.
Prevent foreign substance, such as water, other liquids or chemical, from entering the speakers while
performing maintenance procedures on the speakers.

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Chapter 1 How to Handle Defective Returns
1.1 Overview
Receiving Defective speaker from customers
FUNCTION NG
FUNCTION NG FUNCTION OK
FUNCTION OK
Verifying problems
proceeding necessary
tests
Analyzing possible, Main function cause
Deciding & Proceeding the Rectification
methods
Replace Necessary defective parts
Verifying problems
Proceeding Necessary
tests
Return the speakers with proper repacking to
customers

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1.2 Problems
Item ItemProblemDescription
1.2.1 No power，LED （indicator）no light
1.2.2 No sound
1.2.3 Right or left channel no sound
1.2.4 Noise
1.2.5 LED indicator no light
1.2.6 Headphone jack output no sound
1.2.7 VR, headphone jack or line-in jack abnormal

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Attention
1.2.1 No power, LED (indicator) unlighted
Problem
Analyze
and
identify
the
causes
Solutions
Please follow the numbered sequence marked within parenthesis given in individual
Flow chat in that this is the best-recommended sequence to rectify the problems.
Defective transformer
Defective or damaged AC
cable or power switch
Or caused by the following:
1. Transformer secondary wire loosely
connected with 1CN1 jack in
SP-HF1255AAMPA.
2. Copper foil of SP-HF1255A AMP
PCBA broken
Repair or replace Re-solder or replace
No power，LED （indicator）unlighted

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1.2.2 No Sound
Problem
Analyze
and identify
thecauses
Solutions
No Sound
PCB
short-circuited,
dry soldered or
broken
CN1 and CN2 in
AMP board is not
properly connected
Or caused by the
following defective
components
1. U1, U2 in AMP
PCBA
2. VR1，N2，1CN4 in
SP-HF1255A AMP
PCBA
Repair or
Replace
Repair or
Replace
Repair,
re-solder or
Replace

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1.2.3 Right or left channel no sound
Problem
Analyze
and identify
thecauses
Solutions
Right or left channel no sound
PCB damaged,
dry-soldered or
short-circuited;
CN1 in
SP-HF1255A
and CN2 in
SP-HF1255A
AMP PCBA
are loosely
connected
Driver unit or speaker
cable defective or
loosely connected
Audio cable defective
or loosely connected
VR ，N2 or 1CN4
defective in
SP-HF1255A AMP
PCBA
Repair or
Replace
Repair or
Replace
Re-connect,
replace or
repaire

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1.2.4 Noise
Problem
Analyze
and identify
thecauses
Solutions
Noise
Filter capacitor
/diode
dry-soldered or
damaged,
please check
C1, C14, C31，
C20，C9, 1D1，
1D2,1D3, 1D4
in AMP
defective or
not;
The power
supply of each
IC is normal or
not
Or caused by
vibration from too
long lead wire of
driver units
Driver units damaged
Woofer cabinet leaks,
closed not well
Repair
Check and
replace
Repair or
replace