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Depending on radio wave conditions, those most suitable
for FM broadcasts are selected by switch-over of the |F
mode.
e
AUTO DX
When
interference of radio waves is not strong, reception
is made using the wide IF range LOCAL mode. If the radio
waves are weak or jammed, the DX made, which has a
high degree of sensitivity, automatically switches over
enabling reception with little or no static.
Furthermore, in this mode the high cut filter operates in
accordance to the antenna input level. When the radio
- waves become weak, the high filter is activated and high
range noise is eliminated. (In the LOCAL mode the high
filter turns off automatically.)
* Having gone from LOCAL
mode to DX mode once,
even if radio wave conditions revert to normal, return to
LOCAL mode is not automatic.
When this happens, release the control once and reset
the station or use the ENFORCED
LOCAL mode.
e
ENFORCED
DX
To receive from a station far away or when the radio
waves are weak
or jammed,
use of this mode
enables
increased selectivity and clear low-static reception.
e
ENFORCED
LOCAL
This position
should
be used
in areas where the radia
station is nearby and the radio waves are sufficiently
strong with little interference, or when reception of only
strang radio stations and not that of weak ones is desired.
Switch-over
order
RXMODE
e AUTO DX MODE
RAXMODE
RXMUDE
Ox
LOCAL
-
ox
LOCAL
'
C
-EWS
<automatic | EE-
C
auro"
| *
l AUTO
i "|
9
5
ES
(High Cut Filter Auto)
® ENFORCED
DX MODE
RXMODE
OX
LOCAL
-Bem
Co
,
|
"| aura
(High Cut Filter OFF)
C7
e ENFORCED
LOCAL MODE
(High Cut Filter OFF)
Switches are made in the above order
each
time the switch
is pushed
(effective only for FM reception).
Normally
operate
in the AUTO
DX
mode.
Multipath is an effect similar to television ghosting; it
distorts the received signal and alsc causes poor stereo
separation and noise. As shown in fig, radio waves which
travel directly from the transmitter to the receiving antenna
are mixed with waves which reflect off nearby objects such
as buildings. Because the path taken by the reflected waves
is longer than the direct path, the time required for the
waves to arrive at the antenna is also longer. The mixing of
the directly received signal and the delayed signal notice-
ably degrades reception quality. Multipath interference can
be greatly reduced by the use of a high-quality directional
antenna
oriented
in the proper direction.
® MULTIPATH
DETECTION
The signal quality indicator of this unit uses a jamming
detector which shows the quality of radio wave reception
when the MULTIPATH
switch is OFF (indicator light out).
If the MULTIPATH
switch is ON (indicator light on) when
receiving FM boradcasts, multipath jamming is detected and
indicated.
Because reception is distorted if the multipath is detected,
it is necessary to make adjustments by recorrecting the
height, direction,
and
position
of the antenna
or by
replacing it with a good directional antenna.
Broadcast
antenna
waded
se
es)
ui
Wave received
directly
Outdoor
antenna
=
Reflected
we
wave
LIGHT
SIGNAL
QUALITY
|
/MULTIPATH
~N
a
- MLLTIPATH ~
"o...
40
60
60
Rake
tie
Ge
ieee
CO:
Multipath
jamming
= —J Only works during FM reception
aie
Use when fixing the FM antenna positiort
qu
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