Technics SUA 900 Mk2 Service Manual

Page 2

SU-A900MK2

I Contents

I Before Repair ......
0 Protection Circuitry.
OAccessories.........
0 Caution for Mains Lead.
0 From Panel Controls
0 Connections ........
0 Listening to Sound .
0 Recording ............
oOperation Check and

Main Component Replacement Procedures............................. 10~13

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0 Schematic Diagram . .............
0 Printed Circuit Board Diagram.
_ OWiring Connection Diagram ,
0 Block Diagram .....
0 Function of it) Terminals
0 Replacement Parts List .
0 Cabinet Parts Location
0 Packaging ...............

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I Before Repair

(1) Turn off the power supply. Using a 10 Q. 10 W resistor. connect both ends of power supply capacitors (C701. C702) in order to discharge the voltage,
(2) Before turning the power supply on. after completion of repair, slowly appty the primary voltage by using a power supply voltage controller to make
sure that the consumed current at 50/60 Hz in N0 SIGNAL mode should be shown below with respect to supply voltage 110 V/127 V/220 V/240 V.

Power supply voltage AC 230 V AC 240 V AC 110~127 V AC 220~24O V

Consumed current 50Hz 70~270 mA 60-260 mA 120-600 mA 60-260 m

I Protection circuitry

The protection circuitry may have operated if either of the following conditions is noticed:
* No sound is heard when the power is switched ON.
*Sound stops during a performance
The functions of this circuitry is to prevent circuitry damage if, for example. the positive and negative speaker connection wires are shorted". or if
speaker systems with an impedance less than the indicated rated impedance of this unit are used.
if this occurs. follow the procedure outlined below:
1, Switch OFF the power.
2. Determine the cause of the problem and correct it.
3. Switch ON the power once again.

Note:
When the protection circuitry functions. the unit will not operate unless the power is first switched OFF and then ON again.

For aras except (E) (EB) (EG) (G N)
CAUTION:

The Ac voltage differs according to the area.

Be sure to set the proper voltage In your area betor use.

I Accessories

..1

OAC power suppty cord

for (E). (E6) and (GC) areas : (RJA0019-2K) for (EB) area : (VJA0733) for (GN) area : (RJAOOSe-K)

0 Remote control transmitter 0 Batteries 0 Power plug adaptor
(RAK-SU129WH) ...................................... 1 (UM-4. "AAA". R03) 2 (SJP5213-2) .............................................. 1
Note: These are available on sales route. for (GO) area only

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