Technics SUZ 750 950 Service Manual

Page 2

SU-Z750lSU-2950

I CONTENTS

Page
LINE-UP OF COMPONENTS ..................... 2
SAFETY PRECAUTION ....................... 2
LOCATION OF CONTROLS ..................... 3
PROTECTION CIRCUITRY ..................... 4
BEFORE REPAIR AND ADJUSTMENT .............. 4
DISASSEMBLY INSTRUCTIONS ................. 4, 5
OPERATIONAL DESCRIPTION OF |C401 FOR MUTING . . . 6

I LINE-UP OF COMPONENTS

Stereo Integrated Amplifier

SC-D1 30E

Page
CIRCUIT BOARDS AND WIRING CONNECTION
DIAGRAM ........................... 7 ~ 9
TERMINAL GUIDE OF TRANSISTORS, DIODES AND IC'S . . 9
RESISTORS 8: CAPACITORS .................... 10
BLOCK DIAGRAM ....................... 11,12
SCHEMATIC DIAGRAM ................... 13 ~ 15
REPLACEMENT PARTS LIST .................... 16
EXPLODED VIEW ........................ 17, 18

SC-D1ZOE SC-DI 1 0

M;

SU-ZQSO

SU-Z750 SU-ZSSO

Ouartz Synthesizer FM/AM Stereo Tuner

ST-Z550

ST-ZSSO ST-2550

Automatic Turntable System

SL-DZSOU

SL-BZSOU SL-BZSOU

Stereo Double Cassette Deck

1J-

Stereo Graphic Equalizer

RS- DS5OW
SH-2250

RS-D550W RS- D550W
SH-2250

l-li-Fl Speaker SysTems

I SAFETY PRE CAUTION

88-2580

88-2560 88-2520

1. Before servicing, unplug the power cord to prevent an electric shock.

2. When replacing parts, use only manufacturer's recommended components for safety.

3. Check the condition of the power cord. Replace if wear or damage is evident.

4. After servicing, be sure to restore the lead dress, insulation barriers, insulation papers, shields, etc.

5. Before returning the serviced equipment to the customer, be sure to make the following insulation resistance test to
prevent the customer from being exposed to a shock hazard.

o INSULATION RESISTANCE TEST

1. Unplug the power cord and short the two prongs of the plug with a jumper wire.

2. Turn on the power switch.

3. Measure the resistance value with ohmmeter between the jumpered AC plug and each exposed metal cabinet part, such as
screwheads antenna, control shafts, handle brackets, etc. Equipment with antenna terminals should read between 3M0
and 5.2Mfl to all exposed parts. (Fig. A) Equipment without antenna terminals should read approximately infinity to

all exposed parts. (Fig. B)

Note: Some exposed parts may be isolated from the chassis by design. These will read infinity.

Antenna
terminal

(Fig.A)

Ohmmeter

Resistance = auto-5.2 MQ

(Fig.8)
Resistance = Approx 00

4. If the measurement is outside the specified limits, there is a possibility of a shock hazard. The equipment should be
repaired and rechecked before it is returned to the customer.