Technics SUVX 700 Service Manual

Page 2

SU-VX700

I CONTENTS

Page
BEFORE REPAIR AND ADJUSTMENT .................... 2
PROTECTION CIRCUITRY .............................. 2
ACCESSORY .......................................... 2
LOCATION OF CONTROLS .............................. 3, 4
CONNECTIONS ........................................ 4~6
DISASSEMBLY INSTRUCTIONS ........................ 7 ~10
SCHEMATIC DIAGRAM .............................. 11-44

Page
PRINTED CIRCUIT BOARDS ........................ 15~18
WIRING CONNECTION DIAGRAM ........................ 19
BLOCK DIAGRAM ...................................... 20
MEASUREMENTS AND ADJUSTMENTS .................. 21
REPLACEMENT PARTS LIST ...................... 22. 25~27
CABINET PARTS LOCATION .......................... 23, 24
PACKING .............................................. 25

I BEFORE REPAIR AND ADJUSTMENT

(1) Turn oil the power supply. Using a 100, 10 w resistor, shortcircuit both ends of power supply capacitors (0601. 0602) in

order to discharge the voltage.
(2) Betore turning on the power switch of the unit.
A. Connect the voltage controller to the primary side.

B. Connect the AC ampere meter to the primary side or connect the DC voltage meter to the 1-8" circuit of the secondary

side.

C. Turn the VR of I00 (VR451, VR452, VR501 and VR502) to minimum (counterclockwise).
D. After setting the output to zero of the voltage controller, turn on the power switch of the unit.

And increase the output of voltage controller gradually.

Then. check carefully whether the current value of primary side become more than following value or whether the DC

voltage of secondary side is increasing slowly.

E. If the value of current is increasing unusually or the DC voltage is not increasing, lower the output level of voltage

controller immediately.

OThe current value of the primary side at no signal. (Confirm the power supply voltage of each area and provided voltage of

the unit.)

Power supply voltage Ac 230 V AC 240 V
50 Hz 110~210mA 100~200 mA
Consumed current
60 H2 ------- -----

I PROTECTION CIRCUITRY

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

0N0 sound is heard when the power is turned on.

OSound stops during a performance.

The function of this circuitry is to prevent circuitry damage if, tor
example. the positive and negative speaker connection wires are
shorted", or it speaker systems with an impedance less than the
indicated rated impedance of the amplifier are used.

I ACCESSORY

eACpowersupplycords......................... ..
<8FDACOSE03> For (E). (E6) areas.
For (EB) area only.

If this occurs, tollow the procedure outlined below:

1. Turn off the power.

2. Determine the cause of the problem and correct it.
3. Turn on the power once again.

Note:
When the protection circuitry functions. the unit will not operate
unless the power is first turned off and then on again.