Kantronics KPC-2 - Page 37

Calibration/Equalization
The
CALIBRATE
command
is
used
to
assist
the
TNC
operator
in
determining
the
need
for
equalization
of
a
received
signal.
Since
this
feature
is
unique
to
Kantronics
TNCs,
two
stations
using
Kantronics
TNCs
are
necessary
to
utilize
this
command.
KAM
you
must
have
your
current
1/0
stream
on
the
VHF
radio
port.
KPC-4
uses
current
VO
port
(will
not
work
with
an
external
modem).
KPC-2
The
HF,
HFT
and
CCITT
commands
should
be
OFF.
Calibration
is
checked
at
1200
baud
only.
KPC-1
Tones
are
transmitted
and
received
at
the
HBAUD
setting
and
the
frequency
is
specified
by
the
HF
and
HFT
command
settings.
KPC-2400
Tones
are
transmitted
and
received
at
the
HBAUD
setting
and
the
frequency
is
specified
by
the
HF,
HFT,
and
CCITT
command
settings.
However
calibration
cannot
be
done
at
the
HBAUD
setting
of
2400.
Once
the
CALIBRATE
command
is
given,
three
options
will
appear
on
the
terminal
screen:
Calibrate Mode Press R,T, or X
Pressing
X
will
return
the
TNC
to
the
Command
Mode.
Pressing
T
will
transmit
a
square
wave
(space/mark)
at
the
selected
tones
until
a
key
is
pressed.
Pressing R will measure a square wave received.
One
station
should
be
used
to
transmit
the
square
wave,
while
the
receiving
station
should
measure
and
compare
the
space/mark
square
wave.
The
transmitting
station
should
set
the
microphone
level
in
the
mid
range.
Once
the
receiving
TNC
is
placed
in
the
CALIBRATE
receive
mode,
two
numbers
will
appear
on
the
screen.
The
TNC
is
measuring
the
space/mark
square
wave
generated
by
the
transmitting
station.
For
the
best
calibration
of
the
receiving
transceiver,
set
the
radio
tone
controls
so
that
the
two
given
values
are
as
close
to
equal
as
possible.
In
most
instances
when
the
ratio
of
the
numbers
is
within
a
40/60
or
60/40
range,
the
packet
station
will
function
normally.
A
larger
disparity
in
the
tones
may
cause
additional
retries
during
packet
operation.
This
ratio
may
be
determined
by
the
following
formula:
(N1
*
100)
/
(N1
+
N2)
where
Ni
is
the
number
to
the
left
of
the
displayed
slash,
and
N2
is
to
the
right
of
the
slash.
For
instance,
if
the
TNC
displays
1400/1800,
the
ratio
can
be
determined
by:
(1400 * 100) / (1400 + 1800) or 140000/3200 = 44
Since the total is 100, the ratio is then 44/56 and is within the 40/60 criteria.
KPC-1,
KPC-2,
and
KPC-2400.
If
the
ratio
of
the
numbers
exceeds
60/40,
you
should
change
the
setting
of
the
equalization
command
(EQUALIZE).
Use
the
setting
(ON
or
OFF) which
results
in
the
ratio closest to
50/50.
KAM
and
KPC-.
If
the
ratio
of
the
numbers
exceeds
60/40,
you
should
reset
the
internal
Equalization
jumper(s)
for
partial
equalization.
If,
with
partial equalization
these
numbers
are
still
outside
the
60/40
ratio,
set
the
Equalization
jumper
for
NO
equalization.
CALIBRATION/EQUALIZATION 31
© Copyright 1989, Kantronics, Inc. All Rights Reserved.
Duplication
of
this
manual
or
the
firmware
without
-
Version
2.85
permission
of
Kantronics,
Inc.
is
prohibited.
Installation
Manual