RF Concepts RFC 4-110 - Unit Functions; POWER Function; FM-SSB Modes

INSTALLATION
The RFC
4-LLg
can be
mounted
with
ttre
'Lrr
brackets,
supplied.
It
should
be
placed
to
provide
maximum
ventilation
around
the heat
sink.
Heavy
gauge
wire should
be
used
to connect
the
RFC
A'LLA to
the battery
or
power
suppty.
For medium
distances
use
#IO
wire
and
for longer
distances
use
#B
wire.
To connect
the
amplifier
to the
antenna,
RG-8A/U or
equivelent
coax
is recontmended.
For
best
performance,
the
antenna
should
be adjusted
for
an
SWR of less
than
1.5:1.
OPERATION
The
power
amplifier
is connected
between
the radio
and
the
antenna,
The
RFC
4-110
will boost
the
power
of
a
l0
watt
radio
to
LQA
Ylai--ts or
more.
The GaAs-Fet
receiver
Preamp
wiII improve
coPy
on
weak
or
marginal
signals.
When
either the
power
amplifier
or
the
preamp
are
"on"
they automatically
switch
in
and out of
the
circuit,
by
sensing
the
RF from the
radio.
The
rrTxrr
LED
will
light
during
transmit.
The
automatic
switching
is ok
for FM, but on
SSB the relays
may drop out
during
pauses.
Therefore,
it is
high1y
recommended
that
the
external
keying
feature
be
used
with
SSB.
Please see
the
"EXTERNAL
KEYING"
section.
FAULT CONDITIONS
During normal
operation
the
'TXrr
LED
will light
when
the
power
amplifier
is
activated.
The
RFC
4-110
has
a special
circuit
that senses
return
power
(SWR)
from the
antenna.
If this returned
power
exceeds
approximately
25 Watts,
the amptifier
automatically
shuts off,
lighting
the
"SWR"
LED and turning
off the
r'Txrr
LED.
In
order
to
reset
the
amplifier, the
power
on-off
switch must
be switched
off
for
2
seconds
then
turned back on.
WARNINGI
CHECK
OUT
THE
ANTENNA SYSTEM
BEFORE
OPERATING
THE AIVIPLIFIER
AGAIN.
If the heat sink
temperature
exceeds
175
degrees
F. the
internal
thermostat.
will open,
shuting
down the
power
anplifier.
The
rrTxrr
LED will
go
out.
The
thermostat
will automatically
reset
when the
heatsink cools
down.
FUNCTIONS
The
functions of
the RFC
4-11O
are controlled by
the three
front
panel
switches.
POWER
.........
This switch activates
the
power
amplifier section,
as well
as
reseting
the SWR
protection
circuit.
FM-SSB
........
In FM, the amplifier
has a fast
dropout
when the
carrier is removed.
In SSB,
this dropout is