Realistic STA-85 - Page 15

SYMPTOM
CAUSE
AND
REMEDY
17l AM does
not operate.
Damaged
1C401
of Tuner Board
0055
Replace
1C401.
Defective
L4O1, L404,
T401
or T4O2
of Tuner
Board 0055
Replace
the
defective
component(s).
Defective
diode
D401
or D4O2
of Tuner Board
0055
Replace
the defective
diode(s).
One of resistors
of
Tuner Board
0055
Replace
the defective
part.
One of capacitors
of
Tuner Board
0055
Replace
the defective
part.
Selector switch
SW1 defective
Repair
or
replace
the
switch.
Defective
Tuning
Gang
Replace
Tuning
Gang.
Damaged
AM bar
antenna
Repair
or replace
the
bar antenna.
A)
B)
c)
D)
E)
F)
G)
H)
18) LOUDNESS
has no
effect.
A)
Defective LOUDNESS
Switch SWs
Replace
the
switch.
B) Defective
C701 or R703
Replace
defective
component(s).
C) Defective VOLUME
control VR551
or
VR552
Replace.
19)
STEREO-MONO
not
effective
A) Defective
MONO
switch
SW4
Replace
the
switch.
2Ol TAPE MONITOR
noteffective
A)
Defective
TAPE MON
switch
SW3
Replace
the
switch.
B)
Poor
contact in
TAPE lN
input
jacks
Repair
or
replace
jack.
C) Resistor R702
defective
Replace
the resistor.
21!. BASS
control has no
effect.
A) VR902 defective
Replace.
B)
Defective
C908, C909
or R908, R910,
R912 of
Audio
Amp Board
6053.
Replace
the defective
component(s).
221 TREBLE
control has no effect.
A)
VR901
defective
Replace.
B) Defective
C906,
C907, R909, R91
1, R913 of
Audio Amp
Board
6053
Replace
the
defective
component(s).
23t. Excessive
noise
with
PHONO
input A)
B)
Faulty lC 1C501
Replace
the lC.
Faulty
R501, R503, R504
or C501,
C506
Replace
the
faulty
component(s).
15