BendixKing KXP 756 - Manual (Page 16)

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the altitude or greater, this error is
negligible. To obtain accurate ground
speed and time-to-station, the aircraft
must be on a direct course to or from
the VORTAC facility.
Note: It is recommended that the
power to the DME system be turned
on only after engine start-up as this
procedure increases the reliability of
the solid state circuitry.
The KDI 572 Master Indicator
function selector switch serves as the
Power ON-OFF control for the system
as well as selecting the DME
channeling source N1 (NAV 1), Hold
(NAV 1 or NAV 2) and N2 (NAV 2). In
most typical installations, channeling
of the DME is accomplished with the
No. 1 and No. 2 VOR/LOC frequency
selectors in the aircraft. The KDI 573
requires a external panel mounted
switch to provide ON-OFF and NAV 1,
HOLD, NAV 2 Switching.
The DME uses channels that are
paired with VOR/LOC channels.
Tuning the desired VOR/LOC
frequency on the NAV frequency
selector automatically pairs the proper
DME channel. In a few installations, a
separate DME control head is
installed. It selects the VORTAC
channel enabling the DME to function
separately from the aircraft's NAV
system.
Information on VORTAC stations
can be found by checking the current
aeronautical chart.
One or two frequency selector
controls may be used with the KDI
572/574 Master Indicator. The KDI
572/574 also provides a Hold function.
After a DME channel has been
selected, the Hold function may be
selected. This will uncouple the
frequency selector control from the
DME and allow a new navigation fre-
quency to be selected without chan-
neling the DME until the N1 (NAV 1)
or N2 (NAV 2) function is again
selected on the KDI 572/574. This
feature may be used to advantage
during an approach where both NAV
receivers are tuned to the ILS
frequency. If there is no
corresponding DME channel on the
ILS frequency, the DME may be
channeled to a nearby VORTAC
station before the approach is begun
and then placed in Hold position
where it will remain giving useful
distance information up to the time of
loss of signal.
To prevent the display of false
information the KDI 572/574 will
display “dashes” while in search or if
power is turned on or momentarily
interrupted while in the frequency Hold
mode, indicating loss of the DME
holding frequency. Normal operation
is re-established by placing the
indicator function switch in the N1
(NAV 1) or N2 (NAV 2) position. A “1”
(one) is displayed when N1 or a “2”
(two) is displayed when N2 has been
selected as the channeling source. In
the Hold mode either a “1H” or “H2” is
displayed to indicate the channeling
source being held.
The indicator will display “RNV”
when the displayed range, ground
speed and time-to-station are derived
from an area navigation system.
The KDI 572/574 Indicator
displays range to the nearest nautical
mile from 0 to 99.9 nautical miles and
to the nearest 1 nautical mile from 100
to 389 nautical miles. Ground speed
is displayed to the nearest knot from 0
to 999 knots. Time-to-station is
displayed to the nearest minute from 0
to 99 minutes. The display also will
indicate 99 minutes for any computed
time-to-station greater than 99
minutes.
The KDI 573 Slave Indicator (see
Figure) provides a display identical to
the display on the KDI 572 Master
Indicator. An automatic dimming