ICOM IC-756PRO2 Manuale Utente

28

5

RECEIVE AND TRANSMIT

The transceiver has 5 RTTY filters 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 filter is turned ON, the RTTY tuning
meter can be used. (p. 42)

Moreover, the twin peak filter 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 filter ON.

• “TPF” appears when the twin peak filter is turned ON.

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 filter set
mode.

r

Push [(F-1)

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

] to select twin peak filter item.

• The received audio volume may become greater when

the twin peak filter 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 filter set mode.

BW

BW

350

350

SFT

SFT

0

VFO

VFO

FIL2

FIL2

R T T Y

R T T Y

qw:pp

TX

TX

1

CW

CW

qr.qpp.pp

21.076.50

21.076.50

TPF

TPF

METER

METER

Po

Po

ANT

ANT

1

[RTTY FIL]

[CW/RTTY]

TPF indicator

■

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.

■

■

CW-R (CW Reverse) mode receives CW signals with
a reverse side CW carrier point like that of LSB and
USB modes.

Use when interfering signals are near a desired signal
and you want to change the interference tone.

q

Push [CW/RTTY] once or twice to select CW
mode.

w

Push [CW/RTTY] for 1 sec. to select CW or CW-R
mode.

• Check the interfering tone.

BFO

1

⁄

3

 octave

Push for 1 sec.

Desired signal
(600 Hz)

Interference
(800 Hz)

BFO

1

⁄

2

 octave

Desired signal
(600 Hz)

Interference
(400 Hz)