Realistic STA-720 - Page 8

FM
RF
AND
IF
ALIGNMENT
For
European
model, the lowest
frequency
of
FM
tuning
range
should
not be below
87.5
MHz.
FM Dummy Antenna
to 300 S2 antenna terminal
of Receiver
Zin
=
50 o
(75
o)
Zout=3OOO
(balanced)
Signal
generator
output
should
be no higher
than necessary
to obtain an
output reading.
Set Selector
switch to
FM.
Signal Generator
deviation: 75kH'z NOTE:
Be
sure to
disconnect
FM
line
cord antenna
during alignment.
STEP
SIGNAL
GENERATOB
COUPLI NG
SIGNAL
GENERATOR
FR
EOUENCY
R ECE IVER
DIAL
SETTI NG
INDICATOR
ADJUSTMENT
Refer Fig.
4.
R EMARKS
'|
Connect to FM
Antenna Termi-
nal thrbugh
FM Dummy
Antenna
(300
O) Fis.
2
90
MHz
(400
Hz Mod.)
90
MHz
AC Voltmeter
connected
to
TAPE
OUT
jack
L1
01
(ANT.
COIL)
L102
(RF
COIL)
L1
04
(OSC.
COIL)
Adjust
for maxi-
mum reading
on
AC Voltmeter.
2 Same
as Step 1
106
MHz
(400
Hz Mod.)
106 MHz
Same
as
Step
1
TClO1
(ANT.
Trimmer)
TC1
02
(RF
Trimmer)
TC103
(OSC.
Trimmer)
Same
as
Step 1
Repeat
steps 1 & 2
until no further
improvement
is
possible.
3
Same
as
Step
1
90
MHz
(400
Hz Mod.)
90 MHz
Same
as
Step
1 T101
flFT)
Same
as
Step
1
4
Same as Step 1
98
MHz
(400
Hz Mod.)
98 MHz
DC Voltmeter
connected
to
Pin
#31
and
TP
on
PCB #OO74A
T201
Adjust tor zero
reading
on
DC
Voltmeter.
5
Same
as
Step
1
98
MHz
(400
Hz Mod.)
98
MHz
Distortion
Meter
connected to
TAPE OUT
jack
T202
Adjust
for mini-
mum distortion.
6 Same
as
Step
I
98
MHz
(400
Hz Mod.)
98
MHz
SIGNAL
STRENGTH
lndicator LED
VR201
Adjust
for
Full
Signal
lndication
with input of
500
pV
7
Same
as
Step 1
(Set
Selector
switch to
FM
MUTE.)
98
MHz
(400
Hz Mod.)
98
MHz
Same
as Step 1 vR202
Adjust
for zero
reading on
AC
Voltmeter with
SG
output
level
of
6
ptV
12s a
(112.5
s,)
150 r,
Fig,2 FM
DUMMY ANTENNA