Technics SUA 900 MkII Service Manual

Page 2

su-AeimMKz

I Contents

0 Before Repair .....
0 Protection Circuitry.
0 Accessories ........
I Caution for Mains Lead .
I Front Panel Controls .
0 Connections .......
0 Listening to Sound .
0 Recording ........................................................................................... 9
0 Operation Check and

Main Component Replacement Procedures ............................ 1 O~13

l Before Repair

Page
1 4~20
21 ~25
26
27
28
29~35
. as, 34

0 Schematic Diagram .............
0 Printed Circuit Board Diagram
0 Vifiring Connection Diagram
I Block Diagram
0 Function of lo Termma
0 Replacement Parts List
0 Cabinet Parts Location.
0 Packaging .........

(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, alter completion of repair. slowly apply the primary voltage by using a power supply voltage controller to make
sure that the consumed current at 50/60 Hz in NO SIGNAL mode should be shown below with respect to supply voltage 110 Vl127 V/220 V/240 V.

Power supply voltage AC 230 V

AC 240V AC 110-427 V AC 220~24D V

Consumed current 50Hz 7o~27o mA

120-500 mA 60~260 mA

60-260 rnA

I Protection circuitry

The protection circuitry may have operated if either of the following conditions is noticed:

at: 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) (GN)
CAUTION:

The AC voltage differs according to the area.

Be sure to set the proper voltage in your area befor use.

l Accessories

oAC power supply cord . 1

for (E), (EG) and (GC) areas : (RJAOO19-2K)

0 Remote control transmitter 0 Batteries

(RAKvSUlZQWH) 1

for (EB) area : (VJAO733)

(UM-4, "AAA", R03) ................................... 2
Note: These are available on sales route.

I-(

for (GN) area : (RJA0036~K)

0 Power plug adaptor
(SJP5213-2) .............................................. 1
for (GC) area only

I-l