Garmin 320A Manual

Mode A/C Transponder
pilot’s guide
GTX 320A
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© 2000 GARMIN Corporation
GARMIN International, Inc.
1200 East 151st Street, Olathe, Kansas 0 2, 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 Corporation
No. 8, Jangshu 2nd 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 trademark of GARMIN Corporation and may not be used without the
express permission of GARMIN Corporation.
October 2000 Part Number 190-00133-09 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 LIABIL-
ITY ARISING UNDER WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICU-
LAR 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, INDIRECT
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 CONSEQUENTIAL
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 320A owner accepts all responsibility for obtaining
the proper licensing before using the transponder
NOTE: The coverage you can expect from the GTX 320A 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 fl ight attitudes
CAUTION: The GTX 320A should be turned off before starting or
shutting down aircraft engine(s)
F
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Function Selector Switch:
The function selector switch is a fi ve position rotary switch. The fi ve positions are:
OFF-Turns off all power to the GTX 320A (the unit should be turned off
before starting aircraft engine(s).
SBY-Turns the transponder on, but when in SBY the unit will not reply
to any interrogations.
ON-The transponder transmits the aircraft’s identifi cation code (Mode A)
but does not include altitude information.
ALT- The transponder transmits the aircraft’s identifi cation code, in Mode
A and pressure altitude (29.92 inches Hg) information in Mode C pro-
vided the aircraft is equipped with an optional altitude encoder. The unit
is normally operated in the ALT position at all times unless otherwise
directed by ATC.
TST-Moving the switch to the TST position tests the reply light. The
function selector is spring loaded and must be held in TST position.
When released, it automatically returns to the ALT position.
Any time the function switch is in the ON or ALT position the tran-
sponder becomes an active part of the Air Traffi c Control Radar Beacon
System (ATCRBS). The transponder also responds to interrogations from
TCAS equipped aircraft.
Function Selection KnobCode Selection Knobs
Ident Button Reply ight
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Code Selector
The code selector consists of four, eight-position switches that provide 4,09 active
identifi cation codes. The code selected should be either a VFR code or a code assigned
by ATC. Regulations require that aircraft equipped with a transponder must operate the
transponder, including Mode C equipment unless otherwise directed by ATC.
When making routine code changes, you should avoid inadvertent selection of codes
7500, 7 00, or 7700 causing momentary false alarms at ground facilities. For example when
switching from code 2700 to code 7200, switch fi rst to 2200 then 7200, NOT to 7700 and
then 7200.
This procedure applies to nondiscrete code 7500 and all discrete codes in the 7 00 and
7700 series (i.e., 7 00 to 7 77, 7700 to 7777) which trigger special indicators in automated
facilities. Only nondiscrete code 7500 will be decoded as the hijack code. An aircraft’s
transponder code is utilized for ATC tracking capability, therefore you should not turn the GTX
320A to SBY when making routine code changes.
Important Codes
1200-The United States VFR Code for any altitude.
7600-Loss of Communications.
7500-Hijacking (Never assigned by ATC without prior notifi cation of the pilot that the
aircraft is subject to unlawful interference).
7700-Emergency.
0000-Military use. Never squawk this Code.
See the Aeronautical Information Manual (AIM) for an explanation and uses of identifi ca-
tion codes.
I ENT Button
On occasion, a controller will request “SQUAWK IDENT” to identify your transponder
return from other aircraft. Respond by momentarily pressing the I ENT button, activating the
Special Position Identifi cation for approximately 20 seconds.
Reply Light
The reply light will blink each time the transponder replies to an interrogation. The reply
light remains illuminated during the IDENT time interval and during TST function.
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