Am Section; Lw Section; Band Cover; Tracking And Sensitivity - JVC R-X40 Service Manual

AM(MWI Section
Band Cover
1.
Press
to
AM(MW) positign.
2.
Set
the frequency display to 520 kHz
(10
kHz channel
step),
or
522kHz (9 kHz
channel
stepl.
3.
Connect DC.
VTVM. to
test
point
117 and
GND.
4. Adjust
L203
so
that the
VWM.
shorvs
0.85
V.
5. And
set
the frequency display
to
1710 kHz (10
kHz
ctannel step),
or
1611
kHz (9 kHz
channel step).
6. Adiust
G246 so
that the
DC.
VTVM.
reads
9.00 V
for
1710
kHz, or
7.50
V
for
1611
kHz.
Tracking
and
Semitivity
1.
Connect
the RF generator
to
the
antenna
terminal on
the rear panel.
2.
Set
the generator
to
600
kHz (or 603 kHz) with
30
%
modulation
at
400 Hz.
Set
the frequency
display
to 600 kHz, or 603
kHz-
Adiust the core
of ferrite
bar antenna
to
maximize the
output.
Set
the
generator to 14fl)
kHz,
or
14O4
kHz.
Set
the
frequency display
of
the
unit
to
1400
kHz,
or
14O4
kHz.
Adjust
C202 so
that the output
signal
is
maximized.
Repeat these adjustments
(1
- 7)
alternatery
untill
maximum sensitivity
is
obtained.
LW
Seetion
Band GoYer
1.
Press
to
LW
position.
2.
Set
the frequency
display
to
153 kHz.
3.
Connect
a
DC.
VTVM. to test points
116 and GND.
4.
Adjust L2(X
so
that
the
VTVM.
shows 1.20
V.
5.
Set
the frequency
display
to
360 kHz.
6.
Adjust C251
so
that
the
VTVM.
reads
8.00
V.
Tracking and Sensitivity
1.
Connect
the RF generator
to
the
antenna
terminal
on
the rear panel.
2. Set the generator
to
164 kHz
with
30 % modulation
at
4(X)
Hz.
Set
the frequency
display
to
104
kHz.
Adiust
the
core
of
ferrite bar
antenna
to
maximize
the
output.
Set
the frequency generator to 353 kHz.
Set
the frequency
display
of the unit to 353 kHz.
Adiust
C209
so
that the output
signal is
maximized.
Repeat these adjustments (1
-7)
alternatery untill
maximum selectivity
is
obtained.
3.
4.
5.
6.
7.
8.
3.
4.
5.
6.
7.
8.
R-X40
/
R-X40L
No.26O3
-7-