Technics SACH 750 Service Manual

Page 2

SA-CH750

l GEN E HAL
Power consumption 175 W
Power supply
For (E), (E6) areas
For (EB), (GN) areas

AC 50/60 HZ. 230 V
AC 50/60 H2, 230 V-~240 V

Dimension (WXHXD) 270x119x334 mm
Weight 5.5 kg

Notes:
1 . Specifications are subject to change without notice.

For (GO) area AC 50/60 Hz, 1 10/127/220/240 V 2. Weight and dimensions are approximate.
3. Total harmonic distortion is measured by the digital spectrum

I CONTENTS We"

Page Page
OBEFORE REPAIR ........................... . ............ 2 OSCHEMATIC DIAGRAM ............................ 14~22
OPROTECTION CIRCUITRY ...... IPRINTED CIRCUIT BOARD DIAGRAM ................ 23~27
IACCESSORIES ............ OWIRING CONNECTION DIAGRAM
OLOCATION OF CONTROLS IBLOCK DIAGRAM .................. '
ISTACKING THE COMPONENTS .. OFUNCTION OF IC TERMINALS ....
ICONNECTIONS ............ OREPLACEMENT PARTS LIST
OSE'I'I'ING THE TIME OF DAY .. ICABINET PARTS LOCATION ..
ODISASSEMBLY INSTRUCTIONS .. ............. IPACKAGING ...

I BEFORE REPAIR

(1) Turn off the power supply. Using a 100, 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 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 is mode should be shown below with respect to supply voltage 230 V/240 V.

AC 230 V
130~230 rnA

AC 240V
110~21O mA

Power supply voltage

Consumed current 50 Hz

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 0N again

I ACCESSORIES

Check the packing carton for these accessories. .

(RJA0019-2K) for (E), (EG), (GC) areas
(VJA0733) for (EB) area
(SJA173) for (GN) area

ISurround speaker cords ........... , .................. 2 pcs. .
(RJLi P001 1325) for (GO), (GN) areas

(RAK-SC709WH)
ORemote control transmitter ......................... 1 pc.

Note: These are available on sale route.
tFtemote control batteries
UM-4, AAA, nos ................................. 2 pcs.

(REXO462) (SMA233-1 M)

IFlat cable ....................................... 1 pc. IAntenna holder ................................... 1 pc.