Technics SU-A808 User manual

AD9907181C2
Stereo Integrated Amplifier
SU-A808
Colour
(K)...............Black Type
Areas
(E)...............Europe and Russia.
(EB)............Great Britain.
(EG)............Germany, France and Italy.
SPECIFICATIONS
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1999 Matsushita ElectricIndustrial Co., Ltd. All rights reserved.
Unauthorized copying and distribution isaviolation of law.
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NOTATION PUBLIC "-//ALDUS//NOTATION TAGGED IMAGE FILE FORMAT//EN"
ENTITY SYSTEM "C:\WINDOWS\ 礁寞踢\AD_SGML\F9907-3\sea909se\technics.tif"
1. Before Repair
1. Turn off the power supply. Using a10 , 10 Wresistor, connect
both ends of power supplycapacitors (C701, C702) inorder to
discharge the voltage.
2. Before turning the power supplyon, after completion of repair,
slowlyapplythe primaryvoltage byusing apower supplyvoltage
controller to make sure that the consumed current at 50 HzinNO
SIGNALmode shouldbe shownbelow with respect to supply
voltage 230/240 V.
Powersupply
voltage AC 230 V, 50 Hz AC 240 V, 50 Hz
Consumed
current 70-270 mA 60-260 mA
2. Protection Circuitry
The protection circuitrymayhave operatedif eitherof the following conditions is noticed:
-Nosound isheard when the power isswitched ON.
-Sound stops during aperformance.
The functions of this circuitryis toprevent circuitrydamage if, forexample, the positive and
negative speakerconnection wires are shorted, orif speakersystems withanimpedance less
thanthe indicatedratedimpedance of this unit are used.
If this occurs, followthe procedure outlinedbellow:
1. Switch OFF the power.
2. Determine the cause of the problem and correct it.
3. Switch ONthe power once again.
Note:
When the protection circuitryfunctions, the unitwill not operate
unless the power isfirst switched OFF and ONagain.
3. Accessories
-AC mains lead
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(E) and (EG)areas :(RJA0019-X)......... 1pc.
(EB)area :(RJA0053-2X).........................1pc.
-Remote control transmitter
(RAK-SUA11WH)........................................1pc.
-Batteries
(R6/LR6, AA, UM-3)..................................2pcs.
Note: These are availableon sales route.
4. Caution for AC Mains Lead
NOTATION PUBLIC "-//ALDUS//NOTATION TAGGED IMAGE FILE FORMAT//EN"
ENTITY SYSTEM "ac_caution.tif"
5. Operations
6. Operation Checks and Component Replacement /
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Procedures
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7. About the +/- 15 V Line Abnormality Detect
Function
1. Thismodel features the function that shuts downthe mainpower
source when itcheck the ± 15 Vline with the IC801
(microcomputer) and find the different voltage. (After power is
turned on, the unitenters the stand-bymode.)
2. When the unitenters stand-bymode with abnormalitydetected,
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check the circuits arround the ± 15 Vline. (Speciallycheck the
abnormalityof the stabilizing power source circuit.)
3. To clear thisstand-bymode, short-circuitthe TP801 land on the
circuitboard. However, clearance of the stand-bymode and turn
on the electricitywhen the repairisnot completed maylead to
another trouble. Therefore, be especiallycareful to do so. (Donot
turn on the electricityfor along time.)
4. When the repairiscompleted, leave the TP801 open.
7.1. About the abnormalitydetect function with the operation LED
turned off
1. Ifthe operation LEDisturned off, there are possibilities of the
following abnormalities inaddition to the LEDitselfmalfunctioning
:
-Power amplifier´s malfunction bythe speaker terminal short-
circuit.
-Malfunction of cooling fan.
The unitfeatures the function that detects above abnormalities.
8. Schematic Diagram
8.1. SchematicDiagram Notes
-Thisschematicdiagram maybe modified at anytime with the
development of new technology.
Notes:
S204:
Uniton/off switch ( /I)
S801:
Input select switch (TAPE 1)
S802:
Input select switch (TAPE 2/MD)
S803:
Input select switch (AUX)
S804:
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