Garmin GTX 327 Manual

Mode A/C Transponder
pilot’s guide
GTX 327
GTX 327 Pilot Guide.p65 2/23/00, 3:32 PM1

© 2000 GARMIN Corporation
GARMIN International, Inc.
1200 East 151
st
Street, Olathe, Kansas 66062, U.S.A.
Tel. [phone] or 800/800.1020
Fax [phone]
GARMIN (Europe) Ltd.
Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9AQ, U.K.
Tel. [phone]
Fax [phone]
GARMIN (Asia) Corporation
No. 68, Jangshu 2
nd
Road, Shijr, Taipei County, Taiwan
Tel. [phone]
Fax [phone]
Website Address: www.garmin.com
All rights reserved. Except as expressly provided herein, no part of this manual may be
reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium,
for any purpose without prior written consent of GARMIN Corporation. GARMIN Corporation
hereby grants permission to download a single copy of this manual onto a hard drive or other
electronic storage medium to be viewed for personal use, provided that such electronic or
printed copy of this manual contains the complete text of this copyright notice and provided
further that any unauthorized commercial distribution of this manual is strictly prohibited.
Information in this manual is subject to change without notice. GARMIN Corporation reserves
the right to change or improve its products and to make changes in the content without
obligation to notify any person or organization of such changes. Visit the GARMIN website
(www.garmin.com) for current updates and supplemental information concerning the use and
operation of this and other GARMIN products.
GARMIN is a registered trademarks of GARMIN Corporation and may not be used without the
express permission of GARMIN Corporation.
February 2000 Part Number 190-00187-00 Rev. A Printed in USA
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Limited Warranty
GARMIN Corporation warrants this product to be free from defects in materials and
workmanship for one year from the date of purchase. GARMIN will, at its sole option, repair or
replace any components which fail in normal use. Such repairs or replacement will be made at
no charge to the customer for parts or labor. The customer is, however, responsible for any
transportation costs. This warranty does not cover failures due to abuse, misuse, accident or
unauthorized alteration or repairs.
THE WARRANTIES AND REMEDIES CONTAINED HEREIN ARE EXCLUSIVE AND IN
LIEU OF ALL OTHER WARRANTIES EXPRESSED OR IMPLIED, INCLUDING ANY
LIABILITY ARISING UNDER WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE, STATUTORY OR OTHERWISE. THIS WARRANTY GIVES YOU
SPECIFIC LEGAL RIGHTS, WHICH MAY VARY FROM STATE TO STATE.
IN NO EVENT SHALL GARMIN BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDI-
RECT OR CONSEQUENTIAL DAMAGES, WHETHER RESULTING FROM THE USE,
MISUSE OR INABILITY TO USE THIS PRODUCT OR FROM DEFECTS IN THE PRODUCT.
SOME STATES DO NOT ALLOW THE EXCLUSIONS OF INCIDENTAL OR CONSEQUEN-
TIAL DAMAGES, SO THE ABOVE LIMITATIONS MAY NOT APPLY TO YOU.
To obtain warranty service, call the GARMIN Customer Service department (913/397.8200)
for a returned merchandise tracking number. The unit should be securely packaged with the
tracking number clearly marked on the outside of the package, and sent freight prepaid and
insured to a GARMIN warranty service station. A copy of the original sales receipt is required as
the proof of purchase for warranty repairs. GARMIN retains the exclusive right to repair or
replace the unit or software or offer a full refund of the purchase price at its sole discretion.
SUCH REMEDY SHALL BE YOUR SOLE AND EXCLUSIVE REMEDY FOR ANY BREACH OF
WARRANTY.
NOTE: The GTX 327 owner accepts all responsibility for obtaining
the proper licensing before using the transponder.
NOTE: The coverage you can expect from the GTX 327 is limited to
“line of sight”. Low altitude or aircraft antenna shielding by the
aircraft itself may result in reduced range. Range can be improved
by climbing to a higher altitude. It may be possible to minimize
antenna shielding by locating the antenna where dead spots are
only noticed during abnormal flight attitudes.
CAUTION: The GTX 327 should be turned off before starting or
shutting down aircraft engine(s).
F
F
I
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The GTX 327 transponder is powered on by pressing the STBY, ALT or ON keys, or by a remote
avionics master switch (if applicable). After power on a start-up page will be displayed while the
unit performs a self test.
Mode Selection Keys
OFF¾Powers off the GTX 327.
STBY¾Powers on the transponder in standby mode.
At power on the last active identification code will be
selected. When in standby mode, the transponder will not
reply to any interrogations.
ON¾Powers on the transponder in Mode A. At power on the last active identifica-
tion code will be selected. In this mode, the transponder replies to interrogations, as
indicated by the Reply Symbol (). Replies do not include altitude information.
ALT¾Powers on the transponder in Mode A and Mode C. At power on the last
active identification code will be selected. In ALT mode, the transponder replies to
identification and altitude interrogations, as indicated by the Reply Symbol ( ).
Replies to altitude interrogations include the standard pressure altitude received
from an external altitude source, which is not adjusted for barometric pressure. The
ALT mode may be used in aircraft not equipped with the optional altitude encoder;
however, the reply signal will not include altitude information.
GTX 327 Configuration Mode
The GTX 327’s configuration, which is normally done at time of installation, influences
many of the unit’s functions described in this manual. If you wish to view or change any of the
GTX 327 configuration parameters, you may access the GTX 327 Configuration Mode. Use
caution when changing configuration. When in doubt, contact your authorized GARMIN
Aviation Service Center. The Configuration Mode should not be used while the aircraft is
airborne.
To use the GTX 327 Configuration Mode:
1. Press and hold the FUNC key while powering on the unit using the STBY, ON, or ALT key
(or using an avionics master switch).
2. Press the FUNC key to sequence through the configuration pages.
3. Use the CRSR key to highlight selectable fields on each page.
4. When a field is highlighted, enter numeric data using the 0 - 9 keys, and select items from
a list using the 8 or 9 keys.
5. Press the CRSR key to confirm list selections.
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Code Selection
Code selection is done with eight keys (0 – 7) that provide 4,096 active identification
codes. Pushing one of these keys begins the code selection sequence. The new code will not
be activated until the fourth digit is entered. Pressing the CLR key will move the cursor back
to the previous digit. Pressing the CLR key when the cursor is on the first digit of the code, or
pressing the CRSR key during code entry, will remove the cursor and cancel data entry,
restoring the previous code. The numbers 8 and 9 are not used for code entry, only for
entering a Count Down time, and in the Configuration Mode.
Important Codes:
1200¾The VFR code for any altitude in the US (Refer to ICAO standards elsewhere)
7000¾The VFR code commonly used in Europe (Refer to ICAO standards)
7500¾Hijack code (Aircraft is subject to unlawful interference)
7600¾Loss of communications
7700¾Emergency
7777¾Military interceptor operations (Never squawk this code)
0000¾Military use (Not enterable)
Care should be taken not to select the code 7500 and all codes in the 7600-7777 range,
which trigger special indicators in automated facilities. Only the code 7500 will be decoded as
the hijack code. An aircraft’s transponder code (when available) is utilized to enhance the
tracking capabilities of the ATC facility, therefore care should be taken when making routine
code changes.
Keys for Other GTX 327 Functions
IDENT¾Pressing the IDENT key activates the Special Position Identification
(SPI) Pulse for 18 seconds, identifying your transponder return from others on the
air traffic controller’s screen. The word ‘IDENT’ will appear in the upper left corner
of the display while the IDENT mode is active.
VFR¾Sets the transponder code to the pre-programmed VFR code selected in
Configuration Mode (this is set to 1200 at the factory). Pressing the VFR key again
will restore the previous identification code.
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FUNC¾Changes the page shown on the right side of the display. Dis-
played data includes Pressure Altitude, Flight Time, Count Up timer, Count
Down timer, and may include Contrast and Display Brightness, depending
on configuration (as shown in the screens below):
PRESSURE ALT: Displays the altitude data supplied to the GTX 327
in feet, hundreds of feet (i.e., flight level), or meters, depending on
configuration.
FLIGHT TIME: Displays the Flight Time, which is controlled by the
START/STOP key or by a squat switch as configured during installation.
With squat switch control, the timer begins when lift off is sensed and
pauses when landing is sensed.
COUNT UP TIMER: Controlled by START/STOP and CLR keys.
COUNT DOWN TIMER: Controlled by START/STOP, CLR, and CRSR
keys. The initial Count Down time is entered with the 0– 9keys.
CONTRAST: This page is only displayed if manual contrast mode is
selected in Configuration Mode. Contrast is controlled by the 8 and 9 keys .
DISPLAY: This page is only displayed if manual backlighting mode is
selected in Configuration Mode. Backlighting is controlled by the 8 and 9
keys.
START/STOP¾Starts and stops the Count Up and Count Down timers.
CRSR¾Initiates entry of the starting time for the Count Down timer and
cancels transponder code entry.
CLR¾Resets the Count Up and Count Down timers and cancels the
previous keypress during code selection.
8¾Reduces Contrast and Display Brightness when the respective pages are
displayed. Also enters the number eight into the Count Down timer.
9¾Increases Contrast and Display Brightness when the respective pages are
displayed. Also enters the number nine into the Count Down timer.
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Altitude Trend Indicator
When the ‘PRESSURE ALT’ page is displayed, an arrow may be displayed to the right of the
altitude, indicating that the altitude is increasing or decreasing. Of of two sizes of arrows may
be displayed depending on the rate of climb/descent. The sensitivity of these arrows is set
using the GTX 327 Configuration Mode.
Timer Operation
To operate the Flight Timer:
1. Press the FUNC key until ‘FLIGHT TIME’ is displayed.
2. If the GTX 327 is configured as having a squat switch installed, the timer will begin
counting automatically when the squat switch senses that the aircraft has become
airborne.
3. If desired, you may press START/STOP to pause or restart the timer.
4. Press CLR to reset the timer to zero.
5. If the GTX 327 is configured as having a squat switch installed, the timer will pause
automatically when the squat switch senses that the aircraft has touched down.
To operate the Count Up timer:
1. Press the FUNC key until ‘COUNT UP’ is displayed.
2. If necessary, press CLR to reset the Count Up timer to zero.
3. Press START/STOP to count up.
4. Press START/STOP again to pause the timer.
5. Press CLR to reset the timer to zero.
To operate the Count Down timer:
1. Press the FUNC key until ‘COUNT DOWN’ is displayed.
2. Press CRSR and use the 0 - 9 keys to set the initial time. All digits must be entered (use
the 0 key to enter leading zeros).
3. Press START/STOP to count down.
4. Press START/STOP again to pause the timer.
5. When the Count Down timer expires, the words ‘COUNT DOWN’ are replaced with
‘EXPIRED’, and the time begins counting up and flashing.
6. Press CLR to reset the timer to the initial time value.
Automatic ALT/STBY Mode Switching
If the GTX 327 is configured for automatic standby switching, the mode will automatically
change to ALT when a squat switch senses that the aircraft has become airborne. Also, the
mode will change to STBY automatically when a squat switch senses that the aircraft has
touched down. Additionally, a delay time can be set in the Configuration Mode, causing the
GTX 327 to wait a specified length of time after landing before automatically changing to STBY
mode.
GTX 327 Pilot Guide.p65 2/23/00, 3:32 PM7

© 2000 GARMIN Corporation
GARMIN International, Inc.
1200 East 151
st
Street, Olathe, Kansas 66062, U.S.A.
GARMIN (Europe) Ltd.
Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9AQ, U.K.
GARMIN (Asia) Corporation
No. 68, Jangshu 2
nd
Road, Shijr, Taipei County, Taiwan
www.garmin.com
Part Number 190-00187-00 Rev. A
GTX 327 Pilot Guide.p65 2/23/00, 3:32 PM8