ELECRAFT 91
RIT and XIT
You can turn on RIT (receive incremental tuning) by tapping R I T .
The RIT annunciator then turns on. It flashes slowly if you have
selected a wide-range RIT/XIT offset (see R I T menu entry, page
101). The OFFSET knob controls the receive offset.
The +1 and -1 kHz marks on the offset control apply only if the
RIT/XIT range is set to +/- 1.2 kHz using the R I T menu entry.
Regardless of the range used, the exact offset can be determined by
comparing the VFO frequencies with RIT on and off.
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When X I T is turned on, it works similarly to R I T , except that the
transmit frequency is varied with the OFFSET control. This can be
useful for small-split operation (for example, when a DX station
you're listening to says to call "UP 1" kHz), or to adjust your
transmitted frequency at the request of another station. The
transmitted frequency is not displayed during receive mode, so if
you need to determine the exact setting of the offset control when
using
X I T , you can briefly turn on R I T .
It's OK to have both
X I T and R I T on at the same time. In this case
the OFFSET control can be thought of as an extension to the main
tuning knob, but covering only a small frequency range.
As with
S P L I T , if you have R I T or X I T enabled, the transmit
frequency will be displayed when you transmit, and the receive
frequency will be restored a minimum of 1/2 second later.
FINE RIT: In some cases you may want to control the VFO in
smaller steps to fine-tune signals on receive. This can be done using
the FINE RIT feature, described on page 99.
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We did not include detent on the offset knob because experience has shown
that knob detent mechanisms degrade over time, making it difficult to adjust
the offset near the zero point. However, you can always return the offset knob
to the zero point by simply matching the RIT-on and RIT-off frequency
displays, or by turning RIT off.
Automatic Antenna Tuner (ATU)
Both the low-power internal automatic antenna tuner (model
KAT2) and high-power external antenna tuner (KAT100) can
match nearly any coax-fed or random-length antenna on multiple
bands. ATU functions will be covered briefly here; refer to the
specific ATU manual for details.
The operating mode of the KAT2 or KAT100 is selected using the
A T U menu entry, and is normally set to A U T O . The menu entry
also allows you to see the L and C selection, step through ATU
relays, etc. Note: If you have both a KAT2 and a KAT100
connected to your K2, the A T U menu entry will control only the
KAT100. The KAT2 will be placed in through mode (L and C = 0),
and will be set to antenna 1.
The ATU is activated whenever you press
T U N E . The K2 display
will show SWR or forward/reflected power, depending on the tuner's
mode. If a KPA100 is installed, its
T U N E display will be used. Power
is reduced to 2 watts during TUNE mode (20 watts if the KPA100
is enabled). This power reduction can be overridden by holding
T U N E + D I S P L A Y . In this case, no auto-tune will be attempted.
Two antenna jacks are provided on both ATUs, with the matching
network data for both antennas stored on a per-band basis. You can
tap
A N T 1 / 2 to switch antennas. Since the relays take only a small
fraction of a second to switch, it becomes practical to quickly try
both antennas anytime the distant station is weak. This is
particularly useful for Field-Day and similar contests, where you
might use two end-fed random wires running in different directions.
Backup Timer
While you're moving the VFO, a 30-second data backup timer is
being continuously re-started. Once you have completely stopped
tuning the VFO for at least 30 seconds, the K2 will then save your
current operating frequency in EEPROM. As long as you stay on a
particular frequency, no further updates will be done.
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