ACC3. External
filters in external solid-state amplifiers. These
lines Will sink a maximum of
80
mA when
Figure
9
-
Ext. Power Amplifier Connector
activated.
A
20-millisecond delay is provided
to
allow closure
of
the external relays prior to the output
of
RF.
The AMP
PTT
line sinks up
to
250
mA
of current
to activate the external amplifier.
This
output
may be disabled using the Amplifier
Off
selection in the
TX
menu.
EXT ALC
accepts
a
signal from an external output power detector
to
control the output power
of
the transceiver-amplifier system. An increasing voltage on this line Will result in a decreasing
transceiver power output. The detector output needs to have a positive “sense.” The gain
of
detector
is
dependent upon the drive requirement
of the amplifier.
VR
accepts a
DC
input signal provided by an external directional coupler.
This
signal will direct
the transceiver to reduce the transmitter power output during conditions
of
antenna mismatch.
The sense
of
the signal is similar to the
EXT ALC
signal above.
If
the reflected power
is
greater
than
I O
Watts, the forward power
Will
be reduced by whatever amount necessary until the
reflected power
is 10
Watts.
the
The following are also located on the transceiver rear panel.
RJ12 Accessory Connector
-
The
RJ I 2
connector provided on the rear panel
of
the
transceiver provides Connection
to the computer serial port when the control head is mounted
outside
of
the computer (see Figure
3).
The mating cable
to
this
connector
is
not supplied
standard
with
the transceiver but is available from Kachina as part
of the 505ECH kit.
Antenna Ports
-
Two
antenna ports, labeled A and
B,
are
ed on the rear panel
of
the
transceiver. The active port
is
determined by the softwaresettin
within the
control
software. Antenna port data is stored
with
the memory channel and “snapshot” key
(see
“Operation” below). The antenna
port
that was active when the channel
or set-up was stored
Will be reselected whenever the same channel/set-up
is
recalled.
Ground Terminal
-
The transceiver should be properly grounded to a water pipe
or
buried
ground rod. This is especially important
if
the transceiver is equipped with the automatic antenna
tuner module. The system may perform poorly unless the transceiver is properly grounded.
Caution: Due t o risk of
explosion,
NEVER
use
natural
or
L.P.
gas
pipelines
for
grounding
purposes.