Realistic STA-78 - Page 14

SYMPTOM
CAUSE
,'REMEDY
10) Speaker works normally
but
Headphone
does
not
work.
Defective R647
(Left)
or
R648
(Right)
Change it.
Headphone
plug
does not mate with
jack
Replace
the
plug.
1)
2l
11)
All
the
inputs work normally except
"AUX"
input.
1)
Poor
contact in
"AUX"
input
jack
Repair
or
replace
it.
2l
Poor
contact in
SELECTOR Switch
Repair
or replace
the switch.
12)
"PHONO"
input
inoperative 1)
Poor
contact
in
"PHONO"
input
jack
Repair
or
replace
it.
2)
Faulty
SELECTOR
Switch
Repair
or
replace it.
13)
"TAPE
OUT"
inoperative
1)
Poor
contact in
"TAPE
OUT" output
jack
Repair
or replace it.
14)
"TAPE
lN"
inoperative
1)
Poor
contact in
"TAPE
lN" input
jack
Repair
or
replace
the
jack.
15)
"DUB
OUT" inoperative
1)
Poor
contact
"DUB
OUT"
jack
Repair
or replace
the
jack.
16)
No AM
or
FM
(Tuner
+B
voltage
is not
11
-12
V .l
1
)
Broken
tertiary
winding
in
the
Power
Transformer
Replace
the
Transformer.
2)
Defective
Diode
D701
Change the defective diode.
3)
Faulty
capacitor
C7O7,711
or
713
Replace
the defective capacitor
(s).
4) Faulty
resistor R705
or 707
Replace
the
resistor(s).
5l
Zener Diode D704
defective
Replace
the
Diode.
6) Short-circuit in Tuner
+B
circuit
Repair
the short.
7)
Poor
contact in
SELECTOR
Switch
Repair
or
replace
the Switch.
FM
No171
1)
Poor
contact
in
SELECTOR
Switch
Repair
or
replace
it.
2)
lC, Transistor,
diode, resistor,
capacitor, inductor
or
IFT
of
FM
lF
Board
defective
Replace
the defective
part(s).
3)
FM Front End
defective
Replace
the defective
part(s).
4)
Faulty FM
Antenna lead-in/circuitry
Repair
or
replace
the Antenna lead-in/circuitrv.
AMNo18)
1)
Poor
contact in
SELECTOR
Switch
Repair
or replace
Switch.
2)
lC, Transistor,
diode, resistor,
capacitor
or
IFT
of
AM
lF Board
defective
Replace
the defective
part(s).
3)
Bar-Antenna
Coil defective
Repair
or
replace
it.
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