Sansui AU-7700 - TROUBLESHOOTING CHART; Power Supply Section Troubleshooting; Audio Section Troubleshooting

GAU
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4. TROU
BLESHOOTI
NG
CHART
4-1. Troubleshooting
on
Power Supply
Symptom
Check
Point
1.
No
power
supplied to
each section
1-1.
lndicator
lamp
for
power
not
lighted
Section
1-2. lndicator
4-2.
Troubleshooting
on
Audio
Section
"1
.
Rel
ày,
RL01 inoperative
(protector
circu
it inoperative)
2.
Bias current
not adiustable to
*45mA
by
VR03
(L-ch)
or
VR04
(R-ch)
on
t-2097
Center
Voltage
not
adiustable
(L-ch)
or
VR02
(R-ch)
on F-2097
to
0V by
VR01
Cause
&
What to
Do
Power
supply
cord
open
lmperfect
contact
of
power switch,5701
Power
f use,
F701
open
Defective
power transformer,
T701
F07 on
t-2097
open
Defective
D21 on
F'2097
lmperfect
contact
of
voltage
selector,
PUOl
F05 or
F07 on
F2097
open
Defective
D17 or
D19 on
t-2097
Defective
power transformer,
T701
F01
(or
F03) on
t-2092 open
Defective
D01,
D03,
D07 or
D09
on
t-2092
Defective
TR09,
TR11,
TR13
or
TR15
on
t-2092
F07 on
F-2097
open
Defective
D21 on
t-2097
Defective
D13,
D'I5 or
D25 on
t'2097
Defective
TR29,
TR31 or
TR33 on
F-2097
Defective
reluy,
RL01
on
F-2097
Defective
TR21 or
TR23
(TR22
or
TR24)
o
n
F
'2097
Defective
TR25
or
TR27
(TR26
or
TR2B)
on
t-2097
Defective
TR05 or
TR07
(TR06
or
TR0B)
o
n
t'2097
Defective
VR03
(VR04)
on
F'2097
Defective
TR05
(TR06)
on
F-2097
Defective
VR01
(VR02)
on
F'2097
lamp for
power
Iighted
+41Y
not supplied
to
collector
trans
istors
(+
41V
,
TR21
,-TR24,
1.
2.
3.
4.
5.
6.
7.
B
1)
on each
power
-
41V
,
TR25
-
TR2B)
2)
+24V not supplied to
terminal
not
supplied to terminal
tr
on
@
and
-2sV
F-2092
L_;
10.
11.
12.
13.
V,
\t
3.
10
L-;;
1.
2.
3.
5