BendixKing KXP 756 - Manual (Page 19)

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management of the TACAN derived
steering signal when dual tuning
sources (and dual HOLD sources)
exist.
A typical installation may have
the TACAN tuning source designated
as the NAV 1 control head whereby
the pilot associates this tuning source
with the number one navigational
display system. Pilot selection of NAV
2 to tune the TACAN will now remove
the TACAN derived steering
information from the number one NAV
display. This action allows only the
steering information obtained from the
number one tuning source to be
displayed on the number one NAV
display. Pilot selection of NAV 1
HOLD will also remove the steering
information from the NAV 1 steering
display. This action prevents the
operator from associating a retuned-
during-HOLD frequency on the NAV 1
tuning head with the tune-before-
HOLD steering information displayed
had that steering information been
presented. The TACAN may use
channels that are paired with
VOR/LOC channels. Tuning the
desired VOR/LOC frequency on the
NAV frequency selector automatically
pairs the proper TACAN channel.
Table 2 shows VOR frequency to
TACAN channel and frequency
conversion. In certain installations, a
separate TACAN control head is
installed. It selects the TACAN or
VORTAC channel enabling the unit to
function separately from the aircraft's
NAV system. The number of channels
is limited to 200 if tuning is accomp-
lished using a NAV control head. A
TACAN control head will tune all 252
channels. This unit selects TACAN
channels 1 thru 126, X or Y. To tune a
VORTAC station, one must know the
channel number of the corresponding
VOR frequency. Refer to
Table 2 .
Information on TACAN and
VORTAC ground stations may be
found in the current aeronautical chart.
Bearing information may be
displayed on the KI 203 or KI 229
indicator. The KTU 709 provides a
TACAN derived composite output
which can directly drive most VOR
indicators. Because it operates at
microwave frequencies, the KTU
709's TACAN bearing signal is less
subject to erratic behavior such as
VOR “scalloping". It is also less
affected by helicopter rotor modula-
tion and is less prone to reflected
signal distortions than VOR.
The KTU 709 provides echo
monitoring and protection. It also
features self-test modes for both
bearing and range. Self-test modes
may be used to checkout the system
prior to installation or as an in-flight
test to verify the system is functioning
properly. The KTU 709 TACAN
system provides an audio capability
allowing the pilot to identify the
TACAN or VORTAC ground station by
listening to the ID tones transmitted by
the ground station at 30-second
intervals.