Kantronics KPC-2 - Page 25

AFSK Output Level
Auf Audio Frequency Shift Keying
Jumpers are appropriately labeled on the PC board. Refer to the parts location
diagram for help in locating them. Also refer to the Assembly and Disassembly section
for information on obtaining access to the interior of the TNC.
KAM - AFSK Output - VHF - Jumper K2
This jumper is provided to alter the VHF AFSK output level. The KAM is shipped from
the factory with the jumper in the LO position. The LO position sets an AFSK output
level from the KAM at 10 mV. The HI position sets an AFSK output level of 50 mV.
Both levels are peak-to-peak values. In general, transceivers requiring a pre-amplified
microphone will also require the HI level AFSK output from the KAM. Removing the
jumper entirely will provide the maximum possible output level of approximately 1.7
P/P volts VHF. Should you require an intermediate value of AFSK modulation signal, it
may be obtained by replacing resistor R12 with the appropriate value chosen from the
following chart. If you change R12 to obtain an intermediate value, place K2 in the
HIGH position.
R12Value AFSK Output Level
470 ohms 24 mV
2.2Kohms 106 mV
6.8 Kohms 290 mV
Kohms 680 m󰾰 22 جم
Kohms 1000 mV󰾰 47
KAM - AFSK Output - HF - Jumper K5󰾰
This
jumper
is
provided
to
alter
the
HF
AFSK
output
level.
The
KAM
is
shipped󰾰
from
the
factory
with
the
jumper
in
the
LO
position.
The
LO
position
sets
an
AFSK󰾰
output
of
100
mV.
The
HI
position
sets
the
output
level
at
500
mV.
Both
levels
are󰾰
peak-to-peak
values.
In
general,
transceivers
requiring
a
pre-amplified
microphone󰾰
will
also
require
the
HI
level
AFSK
output
from
the
KAM.
Removing
the
jumper󰾰
entirely
will
provide
the
maximum
possible
output
level
of
approximately
1.6
volts󰾰
P/P.
Should
you
require
an
intermediate
value
of
AFSK
modulation
signal,
it
may
be󰾰
obtained
by
replacing
resistor
R25
with
the
appropriate
value
chosen
from
the󰾰
following
chart.
If
you
change
R25
to
obtain
an
intermediate
level,
place
K5
in
the󰾰
HIGH position.󰾰
R25 Value AFSK Output Level󰾰
ohms 48 mV󰾰 680
Kohms 209 mV󰾰 3.3
Kohms 282 mV󰾰 4.7
Kohms 377 mV󰾰 6.8
Kohm 800 mV󰾰 22
©
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
"NN