Sony STR-N500 - 2 Electrical

SECTION 2
ELECTRICAL
ADJUSTMENTS
Note:
As
a
front-end
(FE1)
is difficult
to
repair
if
faulty,
replace
it
with
new
one.
The
FM
TUNED
level
must
be
adjusted
after
the
AM
TUNED
level
adjustment
has
completed.
AM Section Adjustment
Setting:
loop antenna B
loop antenna A
a (i)
i
AM ANTENNA
terminal
(TM1)
Carrier
frequency:
999
kHz
(except
E
model)
: 1,000 kHz (E model)
Modulation: 400 Hz, 30% modulation
AM RF signal
generator
AM tuned Level Adjustment
Band: AM
Procedure:
1.
Set
loop
antenna
A
so
that
the
loop
antenna
B
input
level
becomes
316
wV
(50
dB
yz).
2.
Tune
the
set
to
999
kHz
(except
E
model)
or
1,000
kHz
(E
model).
3.
Adjust
RV1
so
that
the
TUNED
indicator
goes
on.
Adjustment Location: main board
FM Section Adjustment
Setting:
FM RFF stereo signal
generator
75 Q coaxial
Carrier frequency: 98 MHz
Modulation: 1 kHz, 75 kHz deviation
FM ANTENNA terminal
(T™M1)
FM Tuned Level Adjustment
Band: FM
Procedure:
1.
Supply
a
17.8
wV
(25
dB)
98
MHz
signal
from
the
ANTENNA
terminal.
2. Tune the set to 98 MHz.
3.
Adjust
RV2
so
that
the
TUNED
indicator
goes
on.
Adjustment Location: main board
FM POLAR Adjustment
Setting:
Band: FM
FM FF signal generator
75 Q coaxial
Carrier frequency: 69 MHz
Output
level:
1
mV
(60
GB
1)
EM
ANTENNA
terminal
1.
Connect
the
frequency
counter
to
the
TP102
and
adjust
the
RV102
for
a
frequency
of
31.25
kHz
+
50
Hz.
2.
Connect
the
VIVM
to
the
TP101,
receive
the
signal
of
69
MHz
+1
kHz
(1
kHz
dev.)
and
adjust
the
reading
of
the
VTVM
to
0
dB.
3.
Set
the
modulation
frequency
of
the
FM
RF
signal
generator
to
31.25
kHz
(10
kHz
dev.)
and
adjust
the
L101
so
that
the
reading
of
the
VTVM
is
0
GB.
4.
Adjust
the
RV101
so
that
the
reading
of
the
VTVM
to
14
dB.
5.
Check
that
the
separation
between
Pins
©
and
@
of
the
IC102
is
more
than
18
dB.
Adjustment Location: main board
(MAIN BOARD] (Component Side)
AM TUNED
LEVEL ADJ FM TUNED
RV1 Ics LEVEL ADJ
[dave
4
i)
FM POLAR ADJ