Kantronics KPC-4 - Page 50

which
could
be
decoded
by
selecting
MODEM
SHIFT,
and
using
the
MARK
and
SPACE
commands
to set
various
tones
until
the
tuning indicator
gives the
proper
indication.
Once you
have
the
proper
tuning indication,
it
is still
possible
that the
signal
may
be
at
the
wrong
baud rate
or
the
signal
may
be
inverted.
If the signal
is
at the
incorrect
speed
(baud
rate)
you may change
your receive speed
while receiving
by using
the
Ctrl-C
n
directive.
If
you
think
the
signal
may
be inverted,
you
can invert
the received
signal
by using
the
Ctrl-C
I
directive.
This
directive
is a
toggle
type
of
operation
—
that
is,
the
first
time will
invert
the
signal, and
a
second
entry will
return
the
signal
to
normal,
Now lets examine each of the commands relating to RTTY and ASCII operation to see
the effect each will have on these modes.
The ASCBAUD command sets the baud rate to be used when entering the ASCII Mode
from the cmd: prompt with no speed specified. This setting is also used to set the baud
rate when the Ctrl-C Ø directive is issued.
AUTOCR will cause the KAM to insert a carriage return sequence after you have
entered n characters without pressing the return key on your keyboard. The KAM
will count all characters, including FIGURES and LETTERS shift characters. The
default setting is 72.
AUTOLF ON causes the KAM to insert a line feed after every carriage return which
is received from the distant station. If received RTTY or ASCII signals appear
double-spaced on your screen, you will want to turn this command OFF.
The AUTOSTRT command is useful if you wish to leave your station in the automatic
mode, in which you can receive messages from other stations, even when you are not
present. With AUTOSTRT ON, a station can cause you to start receiving data by
sending
the
callsign
in
your
MYAUTOST
parameter
(will
accept
up
to
7
characters
allowing for MARS callsigns) prior to sending his message to you. The KAM will stop
receiving
when
it
receives
NNNN
from
the
other
station,
or
when
there
is
no
signal
present for approximately 30 seconds.
The CCITT command controls which RTTY character code will be used in the RTTY
Mode. When this command is OFF (the default) the US RTTY code will be used, and
when ON, the European code (ITA2) will be used. These two codes differ only on four
characters, and the differences are shown here:
US RTTY ITA2
BELL , (comma)
' (apostrophe) BELL
+ "
= .
E ?
A
standard
operating
practice
in
RTTY
is
to
send
a
CR CR
LF
at
the
end
of
each
line
to
allow
the
receiving
station
time
to
return
the
carriage
of
the
mechanical
RTTY
machine
to
the
far
left
edge
of
the
paper
before
sending
the
next
character.
This
can
be
accomplished
by
setting
the
CRADD
command
ON.
This
causes
the
KAM
to
send
an
extra
CR
after
every
CR
transmitted.
This
command
applies
to
ASCII
and
RTTY
Modes
of
operation,
as
well
as
AMTOR.
The DIDDLE command will cause the KAM to send a special diddle character
whenever
you
are
in
the
transmit
mode,
and
no
data
is
being
sent.
The
default
for
the
DIDDLE
command
is
OFF.
This
is
used
to
allow
the
receiving
station
to
tune
your
signal
prior
to
you
sending
data
since
it
causes
both
mark
and
space
signals
to
be
transmitted.
The
standard
diddle
character
in
the
RTTY
Mode
is
the
LTRS
shift,
and in ASCII, a NULL is sent as the diddle character.
42 RTTY/ASCI
A O Copyright 1989, 1990, Kantronics, Inc. All Rights Reserved.
Version
3.0
Aug.
13,
1990
Duplication
of
this
manual
or
the
firmware
without
Operations
Manual
permission
of
Kantronics,
Inc.
is
prohibited.