Sony ICF-2001D - Improving Reception and AM Modes; Antenna Adjustment Techniques; AM Mode Selection; Synchronous Detection Tuning

FOR IMPROVED RECEPTION
ANTENNA ADJUSTMENT
For FM/AIR reception
Pull out the telescopic antenna to expose its swivel base and ad-
just its length, angle and direction for optimum reception. For AIR
reception, extending two sections of the antenna is recommended.
See iflustration (G]-1 on page 5.
For SW reception
Pull out the telescopic antenna to its full length and set it vertically.
See illustration (G]-2 on page 5.
@lf there is a fluorescent lamp just above the set and reception is
noisy, incline and shorten the telescopic antenna.
For MWILW reception
Retract the telescopic antenna. The built-in ferrite bar antenna ac-
tivates. Since this antenna is directional, rotate the set horizontally
for optimum reception, if necessary. See illustration [G]-3 on page
5.
Notes
@!f reception is unsatisfactory with the telescopic antenna or the
built-in ferrite bar antenna, connect an external antenna*. To con-
nect an external antenna, see page 17.
@in vehicles or in buildings, radio reception may be difficult or
noisy. Try listening near a window.
@lf the received sound is distorted or noisy, adjust the antenna
carefully. For AM reception, set the AM ATT selector to LOCAL.
* With certain models, the external antenna jacks are not provided.
HOW TO SELECT AM MODE
Select the appropriate AM mode according to the broadcast or
receiving conditions.
Selected AM mode
“Wide
WIDE NARROW SYNC USB LSB/CW
AM
MW OK
v 8
2
2 x
WIDE: Normally set to this mode for wider selectivity.
NARROW: If reception is interrupted or noisy, set to this mode for
narrower selectivity. Reception wil! be improved.
SYNC: If reception is difficult because of beats from adjacent sta-
tions or distortion due to fading, which frequently occurs dur-
ing AM (LW, MW and SW) reception, set to this mode and pro-
ceed as in “Tuning using synchronous detection”.
USB: For USB (upper sideband) reception. *
LSB/CW: For LSB (lower sideband) or CW (International Morse
Code) reception. *
*
With
certain
models,
USB
and
LSB/CW
receptions
are
not
available
so
these
keys
are
not
provided.
ICF-2001D/2010
TUNING USING SYNCHRONOUS DETECTION
1 Tune in the desired station.
2
Press
the
SYNC
key.
The
SYNC
indication
witl
be
displayed
and
the
UPPER
or
LOWER
SYNC
indicator
will
light
up.
3
Set
the
MANUAL
TUNE
MODE
selector
to
SLOW.
4
Turn
the
MANUAL
TUNING
knob
slowly
so
that
the
other
SYNC
indicator
tights.
Choose
the
best
possible
tuning
point,
monitoring
the
received
sound.
MANUAL
TUNING
306 UPPER aang © UPPER
SYNC > > SYNC
@
LOWER
6
LOWER
To cancel the SYNC mode, press the SYNC key again. The SYNC in-
dication will disappear.
—What is synchronous detection?
There
are
two
big
problems
in
AM
reception:
distortion
due
to
fading
and
interference
from
adjacent
stations.
The
synchro-
nous detection is effective to these problems.
Distortion
due
to
fading
is
caused
by
overmodulation,
which
oc-
curs
when
a
Carrier
component
of
the
received
Signal
is
at-
tenuated
on
the
way.
In
this
receiver,
a
pure
carrier
frequency
with
no
level
variation,
perfectly
synchronized
with
the
original
carrier,
is
generated
in
the
synchronous
detector
circuit
and
is
mixed
with
the
received
signal
to
compensate
the
attenuated
carrier
component.
In
this
way,
distortion
is
remarkably
reduc-
ed.
On the other hand, AM (LW, MW and SW) broadcasting generally
uses double-sideband transmission, in which modulated signals
are transmitted using both the upper and lower sidebands (USB
and LSB). In most cases one of the sidebands is affected by in-
terference from adjacent stations (beats). In the synchronous
detector circuit, one of USB and LSB can be received. This
allows clear reception without interference from adjacent sta-
tions.
Carrier
LSB USB
Interference from
i
adjacent
station
pana
Only this side is
received.