Realistic STA-115 - Page 17

Preamp
Operation
Check
Connect
audio
osc. to PHONO
input.
connect
oscilloscope
and
V.T.V.M.
with
decibel
scale
to
TApE
oUT
jack.
Set
SE
LECTOR
switch
to
pHONO.
Figure 11
(.
l.
[.
"*
RIAA
Curve
**
[loo
n,
-
+
12.9
dB\
(
t
r.Hr-odB
)
\r
o
rHz
-
-13.7
dB
)
(1)
(21
(3)
Figure 12
2o ,@
Auoo
I x
Check
1C301.
Check
C309,
C31 1,
R309, R31
1
(
L ch)
and
C310,
C512, R310,
R31 2
(R
ch).
Check
PRE
amp
circuits.
Equalization
response
at 100 Hz
does not
fallwithin
+
12.g
(RIAA)
!2dB
and 10 kHz
does not
fall
within
-13.7
(RtAA)
t2
dB.
Equalization
response
falls
within
+
12.9
(RIAA)
12
dB
at
100
Hz
and
-13.7
(RIAA)
!2dB
at 10 kHz.
OSCILLOSCOPE
DtroooD!trtrtro
o
T----
L 9 !1"5
_tl'_P_lolo_
:.
g,_u
!.3!
gy9T9
11.:
]
REPAIR
Proceed
to next
section.
-11
-