Realistic STA-115 - Audio Circuit Adjustment

Equipment
Required
1. AC Voltmeter
Set-Up
Figure
25
.
Connect DC
voltmeter to
pin
1 1
(L)
orpin
12
(R)
andGROUND
of
TUNER
AUDIO P.C.B.
Adjustment
Check
Audio
Circuit Adjustment
Notes:
o
Maintain
voltage
a'r. 12O volts
AC, 60 Hz
(U.S.A.,
Canada)
(240
volt
AC,
50
Hz for
Australian models.)
I.-s",;E
L
-r
o; *I..
r,,.-n
u
vrI
l.
S., MONO
switch
to lN
position.
i
Lil.lfgrylolrry, ____
|
TUilER
AUOIO PC.B.
DC VOLTMETER
lffi
r,--Il
Figure
26
o
Connect
DC voltmeter to
R531
(L
ch)
or
R532
(R
ch).
STEP
ADJUSTMENT
EOUIPMENT
LEVEL
ADJUSTMENT/CHECK
1
Check balance by measuring
DC voltage across OUTPUT
terminal of L and
R
channel.
DC voltmeter
(Figure
25)
DC voltage
should
be
less
than
t50mV.
Check:
TR501(L)
TR502(R)
2
I dli ng
current adjustment
for
U.S.A.and Canadian models
DC voltmeter
(Figure
26)
Adjust
voltage
across
emitter
resistors R531
and
R532
to 2.35mV
+4.71-1.88mV
(8O
Load)
Check the value of
R519(L), R520(R).
3
ldling
current adjustment
(for
Australian models)
same as above
same as above
Adjust
VR501
(L),
vR502(R).
-28-