Garmin GTX 330 Mode S Technical specifications

P/N 11934-S28 1 of 8
Cirrus Design Section 9
SR20 Supplements
Pilot’s Operating Handbook and
FAA Approved Airplane Flight Manual
Supplement
for
Garmin GTX 330 Mode S
Transponder
When a Garmin GTX 330 Transponder is installed in the Cirrus Design
SR20, this Supplement is applicable and must be inserted in the
Supplements Section (Section 9) of the Cirrus Design SR20 Pilot’s
Operating Handbook. This document must be carried in the airplane at
all times. Information in this supplement adds to, supersedes, or
deletes information in the basic SR20 Pilot’s Operating Handbook.
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Section 9 Cirrus Design
Supplements SR20
Figure - 1
GTX 330
GARMIN
STBY
OFF
ON
IDENT
VFR
0 1234 567 89
CLR
FUNC
START
STOP
CRSR
ALT
12 3 4 5
678910
1. Identification Key
2. Mode Selector Keys
a. OFF
b. STBY (Standby)
c. ON
d. ALT
3. Display Window
4. FUNC (Function) Key
5. CRSR (Cursor)
6. CLR (Clear) Key
7. START/STOP Key
8. Photocell
9. VFR Key
10. Selector Keys
a. 0-7 - Code Selection
b. 8-9 - Display Brightness/Contrast
ALT 1200 FLIGHT TIME
01:23:20
Garmin GTX 330 Transponder
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P/N 11934-S28 3 of 8
Cirrus Design Section 9
SR20 Supplements
Section 1 - General
The airplane is equipped with a single Garmin GTX 330 ATC Mode S
transponder with IDENT capability. This supplement provides
complete operating instructions for the GTX 330 and does not require
any additional data be carried in the airplane.
Section 2 - Limitations
No Change.
Section 3 - Emergency Procedures
No Change.
Section 4 - Normal Procedures
• Note •
Expected coverage from the GTX 330 is limited to “line of
sight.” Low altitude or aircraft antenna shielding by the
airplane itself may result in reduced range. Range can be
improved by climbing to a higher altitude.
After Engine Start
1. Avionics Power Switch ...............................................................ON
The transponder will turn on in the same mode of operation
selected at the last power down and will display the last entered
identification code.
Before Takeoff
1. Transponder Mode Selector Keys .............................................ALT
If the transponder is in STBY or GND mode, it will automatically
switch to ALT during takeoff when the groundspeed increases
through approximately 35 knots. The transponder will respond to
ATC Mode A/C (altitude and identification) interrogations.
• Note •
Selecting ON puts the transponder in Mode A/S only. The
transponder will respond to Mode C (altitude) interrogations
with signals that contain no altitude information.
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4 of 8 P/N 11934-S28
Section 9 Cirrus Design
Supplements SR20
After Landing
1. Transponder Mode Selector Keys ............................. STBY or OFF
If the transponder is in the ALT or ON mode for landing, and the
airplane is in a Mode S environment, the transponder will
automatically switch to GND during landing rollout when the
groundspeed decreases through approximately 35 knots. If the
airplane is not in a Mode S environment, the transponder will
automatically switch to STBY during landing rollout.
Section 5 - Performance
No Change.
Section 6 - Weight & Balance
No Change.
Section 7 - Systems Description
• Note •
This supplement provides specific procedures for use of the
GTX 330 Transponder in the SR20 and a general description
of the unit. For a detailed description of the GTX 330, refer to
GARMIN GTX 330 Mode S Transponder Pilots Guide, p/n
190-00207-00 Revision A (Sept 2002) or later revision.
The Garmin GTX 330 transponder system consists of an integrated
receiver/transmitter control unit, an antenna, and an altitude digitizer.
In addition to displaying the code, reply symbol, and mode of
operation, the GTX 330 displays pressure altitude. The unit also
features an altitude monitor and flight timers. Depending on how the
transponder is configured (factory set to voice), a voice or tone audio
output announces altitude deviation of more than 200 feet and count
down timer expiration.
• Caution •
The transponder’s configuration, including the unique Mode S
aircraft address, is set at time of installation. Use caution when
modifying the configuration. Do not enter the Configuration
Mode during flight.
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P/N 11934-S28 5 of 8
Cirrus Design Section 9
SR20 Supplements
While providing the usual identification code and pressure altitude
information as Mode A and C transponders, the Mode S transponder
also uses a unique aircraft address to enhance the tracking
capabilities of ATC and other Mode S transponder-equipped aircraft.
The interrogations that ground-based surveillance radar transmit
include the identification information of the target airplane ensuring
that when other aircraft receive the interrogation, they will not respond.
Digitized altitude information is provided by the altitude digitizer
(encoder) plumbed into the airplane static system. The transponder
and integrated controls are mounted in the center console. The
transponder control provides active code display, code selection,
IDENT button, and test functions. The display is daylight readable and
is automatically dimmed through a photocell. The controller buttons
are dimmed through the INST lights control on the instrument panel
bolster. The transponder antenna is mounted on the underside of the
fuselage just aft of the firewall. 28 VDC for transponder operation is
controlled through the Avionics Master Switch on the bolster switch
panel. 28 VDC for receiver, transmitter, and altitude encoder operation
is supplied through the 2-amp ENCODER/XPONDER circuit breaker
on the Avionics Non-Essential.
Reply Light
The reply light is the small reverse video “R” immediately below the
mode annunciation in the display window. The reply light will blink
each time the transponder replies to ground interrogations. The light
will remain on during the 18-second IDENT time interval.
Mode Selector Keys
The mode selector keys are located in a circular arrangement
immediately to the left of the display window. The selected mode is
annunciated at the left side of the display immediately adjacent to the
selector keys. The four positions are:
OFF - Turns off all power to the GTX 330 transponder. The
transponder should be off until the engine is started. Normally, the
transponder can be left in the STBY position and allow the Avionics
Power Switch to control system power.
STBY - Powers the transponder in standby mode. The last active
identification code will be selected. In STBY, the transponder will not
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6 of 8 P/N 11934-S28
Section 9 Cirrus Design
Supplements SR20
reply to any interrogations from an ATC secondary ground surveillance
radar system. This is the normal position for ground operations in the
SR20.
• Note •
Depend on the ATC environment, STBY or GND mode is
automatically entered from ALT or ON mode during landing
ground roll as the groundspeed decreases through 35 knots.
ON - Powers on the GTX 330 in Mode A (identification mode.). The
last active identification code will be selected. In addition to the
airplane’s identification code, the transponder will also reply to altitude
(Mode C) interrogations with signals that do not contain altitude
information.
ALT - Places the transponder in Mode A and Mode C, identification
and altitude respectively. The last active identification code will be
selected. The transponder will respond to interrogations with the
unique aircraft address and standard pressure altitude (29.92 inches
Hg).
• Note •
ALT mode is automatically entered from STBY mode during
takeoff ground roll as the groundspeed increases through 35
knots.
Code Selector Keys
Code selection is accomplished by depressing the eight selector keys
(numbered 0 - 7) located immediately below the display. Any of 4096
active identification codes can be selected. The selected code must be
in accordance with instructions for IFR flight or rules applicable to
transponder utilization for VFR flight.
The airplane’s transponder code is used to enhance tracking capability
by ATC. Therefore, do not switch the transponder to STBY when
making routine code changes.
Input a New Code
1. Use “0 - 7” keys to input the new code. The new code will not be
activated until the last (fourth) digit is entered. Pressing the CLR
key will move the cursor back to the previous digit. Pressing the
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P/N 11934-S28 7 of 8
Cirrus Design Section 9
SR20 Supplements
CRSR key during code entry will remove the cursor and cancel the
entry.
• Note •
When making routine code changes, avoid inadvertent
selection of code 7500 and all codes within the 7600 series
(7600 – 7677) and 7700 series (7700 – 7777). These codes
trigger special indicators in automated facilities. 7500 will be
decoded as the hijack code.
Important Codes
• 1200 – VFR code for any altitude in U.S.
• 7000 – VFR code commonly used in Europe
• 7500 – Hijacking
• 7600 – Loss of communications
• 7700 – Emergency
• 7777 – Military interceptor operations (Never squawk this code)
• 0000 – Military use only (Not enterable)
Function Keys
IDENT Key
Pressing the IDENT button activates the Special Position Identification
(SPI) pulse for approximately 18 seconds allowing ATC to identify your
transponder return from other returns on the controller’s scope. The
Reply annunciator in the display will illuminate during the SPI pulse.
Momentarily press the IDENT key when the controller requests,
“SQUAWK IDENT.”
VFR Key
Pressing the VFR key sets the transponder to the pre-programmed
VFR code selected in the Configuration Mode (factory set to 1200).
Pressing the VFR key a second time will restore the previous
identification code.
FUNC Key
Pressing the FUNC key changes the data shown on the right side of
the display. Pressing the FUNC key a second time will cycle the
display to the next data. Displayed data includes Pressure Altitude,
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Section 9 Cirrus Design
Supplements SR20
Flight Time, Count Up Timer, Count Down Timer, Contrast, and
Display Brightness.
START/STOP Key - Starts and stops the Altitude Monitor, Count Up,
Count Down, and Flight timers. In Configuration Mode, steps through
functions in reverse.
CRSR Key - Initiates starting time entry for the Count Down timer.
Returns cursor to last code digit within five seconds after entry. Selects
changeable fields in Configuration Mode.
CLRL Key - Resets the Count Up, Count Down, and Flight timers.
Cancels the previous keypress during code selection and Count Down
entry. Returns cursor to the fourth code digit within five seconds after
entry.
Function Display
PRESSURE ALT - Displays pressure altitude in feet. An arrow to the
right of the altitude indicates that the airplane is climbing or
descending.
FLIGHT TIME - Displays the flight time. The timer receives
groundspeed from GPS1. Flight time starts when the groundspeed
reaches 35 knots on takeoff and pauses when the groundspeed
descends below 35 knots on landing.
ALT MONITOR - Controlled by START / STOP key. Activates a voice
alarm when altitude limit is exceeded
COUNT UP TIMER - The count up timer is controlled by the START /
STOP key. Pressing the CLR key zeros the display.
COUNT DOWN TIMER - The count down timer is controlled by the
START / STOP key. The CRSR and “0 - 9” keys are used to set the
initial time. Pressing the CLR key resets the timer to the initial value.
CONTRAST - Allows adjustment of display contrast in Configuration
Mode. When CONTRAST is selected, pressing the “8” key reduces
contrast and pressing “9” increases contrast.
DISPLAY - The display function is not available in this installation.
Display brightness is automatically controlled through a photocell in
the front panel.
Original: 07-03-04