Realistic STA-85 - Page 12

TROUBLESHOOTING
SYMPTOM
CAUSE
AND REMEDY
1)
Receiver not
operative;
pilot
lamp
does not light.
A) Faulty AC
power
cord
Replace the
cord.
B) Defect in the
power
switch
Replace the
switch.
C) Broken wire in the
power
transformer.
Replace the
transformer.
D) Broken
power
fuse
Replace
the fuse.
2l Fuse
blows when
power
is turned
on. A)
Power
Transformer T851 defective
Replace the
transformer.
B) Short
in
the
primary
or secondary
of the transformer
circuitry
Repair the
short.
C) Damaged
rectifier D801
Replace
the
rectifier.
D) Short-circuit in the
rectifier
circuit
Repair
the short.
E)
Short
circuit
in
power
transistor
TR609a,
b or
TR610a,
b
Replace the defective transistor and
check circuit.
3)
Pilot
lamp does not light.
A) Defective lamp(s)
Replace
lamp(s).
B)
Open
in the transformer
T851
tertiary
winding
Replace the
transformer.
4)
Pilot
lamp lights
but no
sound
from
either channel.
A) Resistor
R801,
R807, R508, R509, R904 0r R915
open
Replace.
B) Capacitor C507, C508, C801, C802, C807
or C808
defective
Rep lace the
defective capacitor(s).
C) Diode D801 damaged
Replace the diode.
D)
Open
in secondary winding of the
power
trans-
former T851
Rep lace the transformer.
5)
"A"
Speakers do not
work.
A) Speaker switch SW8 defective
Replace
the switch.
6)
"B"
Speakers do
not work.
A)
Speaker switch SW8
defective
Replace the
switch.
12