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D
D
RTTY filter/Twin peak filter
45
4
RECEIVE AND TRANSMIT
The transceiver has 5 RTTY
fi
lters in addition to nor-
mal IF filters. The passband width can be selected
from 1 kHz, 500 Hz, 350 Hz, 300 Hz and 250 Hz.
When the RTTY
fi
lter is turned ON, the RTTY tuning
meter can be used. (p. 47)
Moreover, the twin peak
fi
lter changes the receive fre-
quency response by boosting 2 particular frequencies
(2125 and 2295 Hz)
for better copying of desired RTTY
signals.
q
Push
[CW/RTTY]
once or twice to select RTTY
mode.
w
Push
[RTTY FIL]
to turn the RTTY
fi
lter ON.
• “TPF” appears when the twin peak
fi
lter is turned ON.
• RTTY filter selection
q
Push
[EXIT/SET]
several times to close a multi-
function screen, if necessary.
w
Select RTTY mode.
e
Push
[RTTY FIL]
for 1 sec. to enter RTTY
fi
lter set
mode.
r
Push
[(F-1)
Y
Y
]
to select band width item.
t
Rotate the tuning dial to select the RTTY filter
width from 1 kHz, 500 Hz, 350 Hz, 300 Hz and
250 Hz.
• Push
[(F-3)DEF]
for 1 sec. to select a default value.
y
Push
[(F-2)
Z
Z
]
to select twin peak
fi
lter item.
• The received audio volume may become greater when
the twin peak
fi
lter is turned ON.
u
Rotate the tuning dial to turn the twin peak filter
function ON or OFF.
i
Push
[EXIT/SET]
to exit the RTTY
fi
lter set mode.
BW
BW
350
350
SFT
SFT
0
VFO
VFO
FIL2
FIL2
R T T Y
R T T Y
TX
TX
1
CW
CW
qr.qpp.pp
21.076.50
21.076.50
TPF
TPF
METER
METER
Po
Po
ANT
ANT
1
qw
:
pp
12:00
12:00
TPF indicator
[CW/RTTY]
[RTTY FIL]
[EXIT/SET]
D
D
About RTTY reverse mode
Received characters are occasionally garbled when
the receive signal is reversed between MARK and
SPACE. This reversal can be caused by incorrect
TNC connections, settings, commands, etc.
To receive a reversed RTTY signal correctly, select
RTTY-R (RTTY Reverse) mode.
q
Push
[CW/RTTY]
once or twice to select RTTY
mode.
w
Push
[CW/RTTY]
for 1 sec. to select RTTY or
RTTY-R mode.
• Check the receive signal.
Normal
Reverse
Space
Mark
BFO
Space
Mark
BFO
170 Hz
2125 Hz
170 Hz
2125 Hz