Sansui AU 317 Service Manual

Page 2

1. BLOCK DIAGRAM

Eu Amp maul

mus saw Loun- Volume TnneAmp
Saleclor Monltor s

Pm -
E... L.
We...
0

AC Line

Mic 0 MI: Amp
(w)

High Fllief DC
Power Ann

Prolector Sneak-r:
K'\ A
-o
w. Ame row AMP
an n
rune

Phouet
um;

To Pm Amp

To Power Amn

m...
m I

Yranflormer Block Diagram

2. ADJUSTMENTS

1. Driver Circuit Board Adjustments

(Refer to Fig. 2-1 below)

Note: 1. Master Volume .............

2. Room Temperature

1. DC 0 V adjustment

Minimum
18°C ~28°C
(65°F ~83°F)

3. For adjustment, run the unit for more than 3 minutes
after the power is switched on.

2. Bias Current adjustment

MEASURE OUTPUT ADJUST ADJUST FOR MEASURE OUTPUT ADJUST ADJUST FOR

Speaker Terminal F-2754 Between TP01 (+) and
L'CH between (+) and (-) VR03, VROl DC 0 V LCH TP03 H 51%; DC 10 mV

Speaker Terminal F-2754
R-CH DC 0 V

b t - VR04, VR02 Between TPOZ (+) and

e ween (+) and( ) R-cH TP04 H 5%? DC10 mV

Note: At first, set VROi, VRO3 for L-CH and VROZ, VR04

for R-CH to center position, then make the rough adjust-
ment by VR03, VR04 and fine adjust by VROi, VR02.

Fig. 2-1

Note: 1. By turning adjustment volumes, VROS and VR06,
counterclockwise, the bias current is decreased.
2. In case of adjusting or confirming bias current, avoid
such a measurement that the power transistors are
heated.

3
J"