Terra TRI NAV Manuale utente

OPERATION/INSTALLATION MANUAL
Trimble
2105 Donley
Austin, Texas 78758
(512) 432-0400
PUBLICATION NUMBER 1900-0220-00
PRINTED IN U.S.A.
TRI NAV
COURSE DEVIATION INDICATOR

OPERATION/INSTALLATION MANUAL
Trimble
2105 Donley
Austin, Texas 78758
(512) 432-0400
OCTOBER 14, 1996
PUBLICATION NUMBER 1900-0220-00
REVISION G
PRINTED IN U.S.A.
TRI NAV
COURSE DEVIATION INDICATOR
T-1
Title Page

Revision G
October 14, 1996 TC-1
TRI NAV
COURSE DEVIATION INDICATOR
OWNER/INSTALLATION MANUAL
TABLE OF CONTENTS
SECTION I .................................................................................................................................. 1
1. INTRODUCTION............................................................................................. 1
1.1. SCOPE ................................................................................................. 1
1.2. DESCRIPTION .................................................................................... 1
1.3. SPECIFICATIONS .............................................................................. 1
1.4. PERFORMANCE ................................................................................ 2
1.5. EQUIPMENT SUPPLIED ................................................................... 2
SECTION II................................................................................................................................. 3
2. OPERATION .................................................................................................... 3
2.1. DESCRIPTION .................................................................................... 3
2.2. OPERATION ....................................................................................... 3
2.3. FLYING THE ECDI ............................................................................ 5
SECTION III ............................................................................................................................... 9
3. INSTALLATION .............................................................................................. 9
3.1. GENERAL ........................................................................................... 9
3.2. PREPARATION FOR USED .............................................................. 9
3.3. GENERAL INSTALLATION INSTRUCTIONS
FOR AVIONICS .................................................................................. 9
3.4. MECHANICAL INSTALLATION ................................................... 13
3.5. ELECTRICAL INSTALLATION ..................................................... 13
3.6. ADJUSTMENTS ............................................................................... 19
SECTION IV ............................................................................................................................. 23
4. WARRANTY.................................................................................................. 23

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Revision G
October 14, 1996
SECTION I
1. INTRODUCTION
1.1. SCOPE
This manual provides installation and operating instructions for the TRI NAV Course
Deviation Indicator manufactured by Trimble of Austin, Texas.
1.2. DESCRIPTION
The TRI NAV ECDI is a micro-processor based navigation instrument. It receives standard
navigation and glide slope signals from single or dual navigation receivers and one glide
slope receiver. It processes these signals into a gas discharge display for pilot information.
Electrical output for an autopilot coupler is also provided.
VOR bearings are calculated from the NAV inputs and displayed in numeric form. A
selected OMNI bearing may be compared to the OBS input. The result of this comparison is
a bar type display indicating course deviation.
In the ILS mode localizer signals are received from the NAV receiver and glide slope signals
from the glide slope receiver. These are decoded and the bar display indicates left-right and/
or up-down corrections required to center the aircraft in the approach beam.
1.3. SPECIFICATIONS
Mechanical Specifications
Size: ARINC 3 ATI 4 5/8" long
Weight: 1.25 lbs.
Electrical Specifications
Supply Voltage: 11-32 VDC
Supply Current: 600 mA max at 13.75V
300 mA max at 27.5V
NAV Input Impedance: 1 megohm
NAV Input Level: 50 mV to 10vrms
1.4. PERFORMANCE
Performance
VOR
Accuracy: ±2°
Max. Deflection: 10°= 14 bar deflection

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Revision G
October 14, 1996
1.4. PERFORMANCE (CONTINUED)
VOR/LOC Composite: (In LOC mode) Factory preset to .18Vrms for
Terra by Trimble Tri Nav Indicator
LOCALIZER
Deflection: 7 bars ±1 bar deflection for 0.093 ddm
Centering Error: ±1 bar
GLIDE SLOPE
Flag Input 250 uA
Deflection: 8 bars ±2 bars deflection for 78uA
Centering Error: ±1 bar
Input: 1000 ohm
1.5. EQUIPMENT SUPPLIED
The TRI NAV is shipped with the following equipment:
Description Qty Number
Connector, Receptacle 1 9-2190-171-00
Lockarm 1 9-2190-172-00
Screw, 6-32 x 5/8 Truss hd. 3 9-2806-110-00

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October 14, 1996 3
SECTION II
2. OPERATION
2.1. DESCRIPTION
The TRI NAV is an Electronic Course Deviation Indicator (ECDI) that presents VOR and
ILS navigation information in a dynamic display. The ECDI is unique and very easy to use.
It gives vivid and dynamic presentation of deviation from VOR, localizer and glide slope
course centerline. The display clearly shows the deviation from the desired flight path. You
will find the Terra by Trimble TRI NAV ECDI reads easily and appears readily in your
peripheral vision.
2.2. OPERATION
The OBS course selector is a small knob on the lower left of the instrument. The OBS course
selector is bi-directional two speed continuous control used to set the desired course. The
slow speed rate is approximately one degree per half turn and high speed is 10 degrees per
half turn. This control has no effect on localizer operation other than to provide a reminder
of the desired course or possibly the missed approach VOR bearing.
The course display is a three digit electronic display which indicates the selected course,
bearing “TO” or radial “FROM” the VOR station. Courses from 000 to 359 may be selected
in one degree increments.
The TO/OBS/FR/BC selector switch is normally positioned in the OBS position which
allows the OBS course selector to be active. The TO position causes the course display to
automatically change to give a continuous bearing “TO” the VOR station and the course
deviation bar will not be illuminated. The FROM position causes the course display to
change automatically to indicate continuously the radial “FROM” the VOR station and the
course deviation bar will not be illuminated. During ILS operation, BC may be selected for
making a Back Course Localizer instrument landing.
The mode display is in the upper left quadrant of the display. In VOR, the mode display
indicates “T” for a bearing TO the VOR station and “F” for a radial FROM the VOR station.
When making an instrument approach where only a localizer is present, the mode display will
display an “L” for localizer. When both a glide slope and localizer are present, the mode
display will exhibit an “I” for ILS. Should a back course localizer approach be desired, the
TO/OBS/FR/BC switch shall be set to “FR/BC”, the mode will display a “b” for back course.
When invalid information or no signal is present, the mode display will display an “o” for
OFF.
The course Deviation Bar indicates deviation from the selected course. The ends of the
display bars have arrows to point direction to fly to stay on course. The more display bars
that are illuminated, left or right, up or down, the greater the deviation from course. The
deviation bar is cabable of indicating a full 10degree error left or right. There are 14 light
bars each side of center in the deviation scale; therefore, each bar represents approximately
0.7 degree deviation in the VOR mode. When exactly on course, indication will be by two
vertical bars in the VOR/LOC mode.

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Revision G
October 14, 1996
2.2. OPERATION (CONTINUED)
The display has no meter movements and is entirely electronic. The actual VOR and
localizer course widths at full scale are the same as conventional needle-type instruments;
however, since the scale is larger, smaller off-course indications can be seen which means
that corrections can begin sooner without over-correcting.
The course is displayed in light bar increments or digitally.
The indicator also features two automatic modes that continuously present the radial
“FROM” or bearing “TO” the VOR station.
A switch for TO-FROM control is provided. The TRI NAV has options to include display of
two VOR’s simultaneously. A remote switch is necessary to switch NAV 2 into the NAV 1
position on the display.
The Glide Slope Deviation Bar indicates deviation from the glide slope center line. A
flagged indication for glide slope is no vertical bar(s) illuminated. Also, the mode indicator
will revert to “L” for localizer instead of “I” for ILS.
In the lower right quadrant a second VOR bearing or radial may be digitally displayed. This
allows two different NAV receivers to be displayed on a single indicator. Typically, NAV 1
would be displayed on the OBS deviation bar and NAV 2 would be displayed on the NAV 2
digital radial display. The lower right toggle switch allows you to change the digital window
radial reading “TO” the station bearing TO the VOR station. Selecting FR allows you to
select the “FROM” radial from the VOR station. The lack of a second or NAV 2 signal will
cause the window to read OFF. A remote switch can be installed to transfer NAV 2 to the
NAV 1 position. A digit numeral 2 will light below the OBS/NAV window to indicate this
mode.
When the lower right switch is positioned in the center position a 0 to 10 minute timer is
activated to aid in standard rate turns, etc. The time can be reset by switching up or down
and moving back to center. Time will immediately be restarted from zero and will count
minutes and seconds.
A push-button to the right of the NAV 2 TO/TIME/FR switch has two functions. When the
NAV 1 TO/OBS/FR/BC switch is in the TO or FR position and the OBS/TEST button is
momentarily pushed and then the NAV 1 switch is moved to the OBS position, the unit will
automatically center, putting you right on course center line TO or FROM the VOR station.
This feature saves rotating the OBS knob to find the radial TO or FROM the VOR.

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October 14, 1996 5
2.2. OPERATION (CONTINUED)
When the OBS/TEST push-button is pushed with the NAV 1 switch in the OBS position, the
unit tests all light bars and digital segments. During test, the light bars are strobbed and 8’s
are displayed in each of the digit windows.
2.3. FLYING THE ECDI
A. Finding Aircraft Position
1. Tune desired NAV frequency and identify.
2. Set TO/OBS/FR/BC selector FR.
3. Course display shows radial aircraft is on from the VOR.
B. Tracking Direct to the VOR Station
1. Tune desired NAV frequency and identify.
2. Set TO/OBS/FR/BC selector switch to “TO”.
3. Push OBS/TEST button and immediately switch TO/OBS/FR/BC switch to
OBS; display will center, turn aircraft toward arrow and maintain aircraft on
course “TO” the VOR.
4. Keep course deviation bar centered by making small aircraft heading
changes.
NOTE: Turn aircraft in direction of arrows, i.e., if bar is going left, left
arrow will light, turn left to get back on course.
C. Flying a VOR Airway
1. Tune desired NAV frequency and identify.
2. Determine aircraft position (see A above).
3. Set TO/OBS/FR/BC selector to OBS.
4. Select desired radial with OBS course selector knob.
5. Set up intercept and fly to course radial.
6. When deviation bar centers, turn on course.
D. ILS Approaches
1. Tune desired NAV frequency and identify.
2. Display shows deviation from localizer and glide slope center. That is, if the
deviation bar indicates deviation up, then you need to fly up to return to glide
slope center.
3. The course display may be set to the localizer course as a reminder.

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October 14, 1996
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Figure 2-1
TRI NAV Display
Indice
Altri manuali Terra GPS


















