32
RTTY Dual-Tone Filter (DTF)
Hold
D U AL P B
to turn on the RTT Y dual-tone
filter (DT F). This creates two filters, one centered
on the mark tone, the other on space, which can
often improve RTTY copy. The filter graphic
changes to reflect this (see below).
When DT F is on, the range of the
WI D TH
control is adjusted to better match the
characteristics of the filter. SHIFT , LOCUT and
HICUT are disabled.
The dual-tone filter can be used with
AFS K A
and
FS K D
. T he on/off state of DT F is saved
independently for each of these modes.
FSK Transmit Polarity
You can invert the logic level of the FSK IN line in
FSK D mode using
CONFIG:FSK POL
..
Mic Gain, ALC, and Monitor Level
I
f
you’
r
e
us
i
ng
an
audi
o
-shift transmit mode (
LS B
,
US B
,
DATA A
, or
AFS K A
)
,
you’
l
l
ne
ed
t
o
s
e
t
the
MI C
level while watching the ALC meter.
You can use the same procedure outlined for voice
modes (pg. 28), except that speech compression
should not be used.
In all cases (SSB modes as well as DAT A), you can
optionally use
MO N
to monitor your data
signals. The procedure given for voice modes can
be used (pg. 28). Voice-mode and DAT A-mode
monitor levels are independent.
T he
MI C
setting does not apply to direct
modulation data modes (
FS K D
and
P S K D
),
since no audio is used for transmission. However,
you can still use
MO N
to monitor the signals.
AMTOR / PacTOR
AMT OR, PacT OR and similar modes can reliably
transfer data
–
including e-mail
–
via HF radio
networks. New modes are under development that
may provide even greater reliability. Applications
include maritime mobile and emergency
c
ommuni
ca
t
i
ons
wher
e
t
he
K3’
s
l
i
ght
wei
ght
a
nd
excellent receive performance are advantageous.
General information regarding K3 set up for these
modes appears below.
Frequency stability is important in these modes.
A 1-PPM T CXO is available (KT CXO3-1).
Connec
t
modem
audi
o
I
/
O
t
o
t
he
K3’
s
LI
NE
OUT and LINE IN jacks (for LINE OUT , use
the T IP contact of a stereo plug). A PTT
connection is also usually required. If the
modem operates from 12 V (0.5 A or less), it
can
be
power
ed
f
r
om
t
he
K3’
s
12
VDC
out
pu
t
.
Set up the modem (if applicable). Settings may
vary depending on the data mode being used.
Locate
CONFIG:LIN OUT
and set it to 10. A
different level may be better for your modem.
The
K3’
s
SYNC
DAT
A feature can be used to
minimize T -R delays (it forces the same crystal
filter to be used for both receive and transmit).
Locate
CONFIG:SYNC DT
. Assign it to a
programmable function (e.g., by holding
P F 1
),
then exit the menu.
T ap
MO D E
to select
DATA
.
Select an appropriate data sub-mode by holding
D AT A MD
, then rotating VFO B.
DA TA A
(generic data mode, USB) is used in most cases;
see pg. 31 for alternatives, such as
AFS K A
.
T ap
AF X
to exit the parameter display.
Locate
MAIN:MIC SEL
and set the audio
source for data to
LI NE I N
. Exit the menu.
If you wish to use SYNC DAT A, turn it on by
holding
P F 1
(or the switch used above). The
–
S
icon will appear. A
CONFIG:PTT RLS
value of 10 to 12 may be ideal in this case.
Some modes may have very high duty cycles;
use less than full power output if required.
Refer to your application software for instructions
regarding email set up and other operating details.
Содержание K3
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