GNS 480 (CNX80) Color GPS/Nav/Com Installation Manual September 2004 560-0982-01 Rev A...
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Garmin. Garmin hereby grants permission to download a single copy of this manual and of any revision to this manual onto a hard drive or other electronic storage medium to be viewed for...
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Description 07/13/04 Initial release. 9/15/04 Regulatory compliance clarification. RDERING NFORMATION To receive additional copies of GNS 480 publications, order the following part numbers: GNS 480 Installation Manual 560-0982-xx GNS 480 Pilot Guide 560-0984-xx GNS 480 Reference Guide 560-0989-xx GNS 480 Quick Reference Guide...
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ATTERY EPLACEMENT .............................6-1 ISPLAY ACKLIGHT APPENDIX A - C ........................A-1 ERTIFICATION .......................A-1 NVIRONMENTAL UALIFICATION GNS 480 STC D ............................A-2 APPENDIX B - S ...................B-1 ERIAL NTERFACE PECIFICATIONS ........................B-1 ERIAL NPUT PECIFICATIONS 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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................B-1 ABLE LTITUDE NPUT B- 2 - A ....................... B-2 ABLE ESSAGE ORMAT B- 3 - F (S F )..............B-4 ABLE ESSAGE ORMAT B- 4 - F (Z F ) ..............B-6 GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
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B- 8 - N ..................B-10 ABLE LIGHT AYPOINT B- 9 - F ..................B-11 IST OF LLUSTRATIONS IGURE OLOR 1-1 - GNS 480 C GPS/N ..................1-2 IGURE AMPLE INGLE YSTEM IAGRAM 1-2 - S GNS 480 S ..............1-3 IGURE...
The information in this manual is STC approved. Only the equipment interfaces covered in this manual are within the scope of this STC. Other equipment may be suitable for use with the GNS 480, but use of such equipment is beyond the scope of this STC – additional FAA approval may be required if equipment not covered in this manual is used to interface to the GNS 480.
ESCRIPTION The GNS 480 Color GPS/Nav/Com is a panel-mounted product that contains a GPS/WAAS engine, VHF Comm, and VHF Nav in an integrated unit with a moving map and color display. The GNS 480 will also control a remote transponder.
YSTEM NTERFACES The interfaces for a typical single GNS 480 avionics stack are shown in Figure 1-2, while the interfaces for a typical dual GNS 480 avionics stack are shown in Figure 1-3. The available interfaces are further described in the following sections.
The GNS 480 is capable of driving one external course deviation indicator (CDI) with information based upon VHF Nav or GPS data. The GNS 480 also accepts a resolver input from this CDI. The GNS 480 is capable of driving a second external CDI with information based upon GPS data.
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The GNS 480 has one XYZ synchro input that allows synchro heading to be supplied to the GNS 480. 1.2.2.11 Message Audio Output The GNS 480 has one 500 Ω audio output that can be connected to an audio panel to provide audible messages to the pilot. This output can be automatically inhibited by other equipment if required.
0.7 lbs. (0.3 kg) mounting tube 1.3.3 NVIRONMENTAL The GNS 480 unit is designed and tested to meet appropriate categories as shown in the Environmental Qualification Form included in Appendix A. Operating temperature........-20°C to +55°C Storage temperature ........-55°C to +85°C Temperature variation ........
Position update interval .........0.2 sec (5 Hz) 1 pps (pulse per second) ........±275 nsec of UTC second Datum ............WGS-84 SATCOM compatibility ........Compatible on aircraft equipped with SATCOM Antenna power supply ........35 mA typical, 40 mA max at 4.7 VDC GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
Carrier noise level ......... > 35 dB down Sidetone output ..........up to 280 mW into 100Ω, 120 mW into 500Ω Duty cycle: ............ 100% Stuck mic time-out ........35 second time-out, reverts to receive 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
Receiver sensitivity........-115 dBm typical Centering error..........RTCA DO-195 two sigma limit: 6.6% of full scale GNS 480 performance: less than 1.0% typical (1.5 mV) Audio output ..........With a 1 kHz tone 30% modulation at least 100 mW output into 500 Ω loads Ident/voice .............With 100 mV input, 30% modulation at 1020 Hz,...
Receiver sensitivity ........-95 dBm typical Centering error ..........RTCA DO-195 two sigma limit: 6.7% of full scale GNS 480 performance: less than 2.0% typical (3.0 mV) 1.3.8.4 Computation Rates The tuned active frequency is computed 10 times per second. If the VOR monitor function is activated, 20% of each second is allocated to the monitored frequency, slightly decreasing the active to frequency computation rate.
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Output loading ..........1,000 ohms (max) ILS energize signal ........Sinks up to 400 mA (max) 1.3.9.4 Annunciator Outputs Annunciators..........Open collector outputs capable of sinking up to 400 mA for turning ON annunciator lamps GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 1-11...
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Current:........... 35 mA nominal, 40 mA max. L1 Filter Bandwidth......1575 ±20 MHz (3 dB) +110, -210 MHz (60dB) Group Delay (3dB bandwidth) ....27 ±10 nanosecond Pass Band Ripple (3dB bandwidth) …….0.2 dB max 1-12 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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Current: ...........35 mA nominal, 40 mA max. L1 Filter Bandwidth........1575 ±20 MHz (3 dB) +110, -210 MHz (60dB) Group Delay (3dB bandwidth)....27 ±10 nanosecond Pass Band Ripple (3dB bandwidth) …….0.2 dB max GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 1-13...
AC43.13-1B, Acceptable Methods, Techniques and Practices - Aircraft Inspection and Repair • AC43.13-2A, Acceptable Methods, Techniques and Practices - Aircraft Alterations NOTE Unauthorized changes or modifications to the GNS 480 may void the compliance to required regulations and authorization for continued equipment usage. 1-14 560-0982-01 Rev A...
ATABASE PDATES The GNS 480 utilizes a database stored on a CompactFlash Memory datacard for easy updating and replacement. The database is updated by simply inserting an updated database card into the slot in the front panel in the GNS 480.
The database on the GNS 480 database card is generated from current Jeppesen-Sanderson data and converted to a format that is used by the GNS 480. The data conversion process is performed using software that is developed and maintained under Garmin AT configuration management according to RTCA/DO-200A, Standards for Processing Aeronautical Data.
ACKAGE ONTENTS As shipped from the Garmin AT factory, the GNS 480 package includes most necessary items for installation other than supplies normally available at the installation shop, such as wire and cable ties, circuit breakers, and required input and output equipment. The items included in the package are listed in Table 1-3, Table 1-4, and Table 1-5.
240-0425 #4 SS Flat washer 251-9615-00 Standoff .250sq X .502 long X.075 Note: Hardware Kit items may optionally be provided loose as part of the Installation Kit. Table 1-6 - Optional Equipment Available from Garmin AT Item Description Ω 115-0007...
STAR Standard Terminal Arrival Route Supplementary Type Certificate Temporary Flight Restriction Technical Standard Order Vertical Deviation Indicator VNAV Vertical Navigation Very High Frequency Omni-Directional Range WAAS Wide Area Augmentation System XPDR Transponder GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 1-19...
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General Information OTES 1-20 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
Complete an electrical load analysis in accordance with AC 43.13-1B, Chapter 11, on the aircraft prior to starting modification to ensure aircraft has the ability to carry the GNS 480 load. Refer to Section 2.11 for the power consumption of each GNS 480 mode of operation. Document the results of the electrical load analysis on FAA Form 337.
Installation Procedures 2.3.2 PTIONAL CCESSORIES UPPLIED For a list of optional accessories that are available but not supplied with the GNS 480, refer to Appendix F. 2.4 S PECIAL OOLS EQUIRED Some of the connectors use crimp contacts. The tables below identify crimp tools required to ensure consistent, reliable crimp contact connections for the rear D-sub connectors.
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2.5.1.3 IFR GPS Installation In order for the GNS 480 to be utilized for IFR GPS Navigation, the criteria in 2.5.1.2 must be met and the GNS 480 must be mounted within the acceptable field-of-view. Refer to 2.5.3.1 for determining whether or not the GNS 480 is located within the acceptable field-of-view.
ARINC 429 air data computer (ADC), an SL70/SL70R transponder, a GTX 33/330 transponder, and another GNS 480. If multiple sources of altitude data are supplied to the GNS 480, only valid data from the highest priority source is used (input priority cannot be configured). If the highest priority source becomes unavailable, data is taken from the next-highest priority source.
/ operating the GNS 480. The location should be such that the GNS 480 is not blocked by the glare shield on top, or by the throttles, control yoke, etc. on the bottom.
2. If the GNS 480 is mounted to the right of the instruments, and the left edge of the GNS 480 is within 13.8 inches to the right of the centerline, and the bottom edge of the GNS 480 is in the acceptable area, the GNS 480 is considered within the acceptable field-of-view.
The preferred location for this annunciator is on the same side of the switched CDI/HSI as the GNS 480. A CDI/HSI with a built-in NAV/GPS annunciation may also be used in lieu of a separate external annunciator to satisfy the annunciation requirement.
IEWING NGLE The GNS 480 shall be located such that the operator will have easy access to the controls and have adequate view of the display. The GNS 480 may be adequately viewed from the primary pilot’s position when the following minimums are met: 60 degrees off pilot’s eye center line...
The front of the mounting tube should be flush to the instrument panel and allow sufficient clearance for the back of the bezel of the GNS 480 to mount flush to the mounting tube. Sufficient clearance must exist in the instrument panel opening to allow ease of insertion and removal of the GNS 480.
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(when viewed from the long side of the connector). Straighten the flanges if they are observed to be bowed. Refer to Section 2.7 Electrical Connections for details about how to wire the connectors. 2-10 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
The back of the bezel must be flush to the mounting tube (within 0.020"). If the cam lock is hard to turn or the unit does not seat fully, the unit is probably binding and the mounting tube should be checked. 2-12 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
2.6.4 EPLACEMENT Whenever the GNS 480 is removed and reinstalled, verify that the GNS 480 unit power-up self-test sequence is successfully completed and no failure messages are annunciated. If the unit was serviced or if a different unit is being installed, accomplish the setup and configuration procedures defined in 3.2 prior to verifying that the GNS 480 unit power-up self-test sequence is successfully completed and no failure messages are annunciated.
LECTRICAL ONNECTIONS The GNS 480 installation kit includes four D-sub connectors and three coax connectors. The connector layouts are shown in Figure 2-7. The D-sub connectors use the supplied crimp contacts as specified in Table 2-3. Make the crimp connections with the crimp tool specified Section 2.4.
NOTE The rear connector plate is shown with right-angle RF connectors. Straight RF connectors with female BNC connections (Garmin AT P/N 162-0098) are available as an option, allowing a regular male BNC connector to be used on the antenna cables.
Main Power Output for Nav Receiver 2.8.1 RESERVED RESERVED Power Gnd Out (Nav) Main Power Ground Output for Nav Receiver 2.8.1 VIEW LOOKING AT REAR OF UNIT Figure 2-8 - 37-pin Connector GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 2-17...
2.7.1.2 Com I/O Connector (P4) The GNS 480 communication interface is handled via a standard density male 15-pin D-sub connector located at the top of the unit. Internally this connection is on the VHF COM board. The pinout for the connector is defined in the following table.
2.7.1.3 I/O Expansion Connector (P5) Additional I/O for the GNS 480 is achieved via the I/O expansion connector, which consists of a high density female 78-pin D-sub connector near the bottom of the unit. The pinout for the connector is defined in the following table.
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Discrete In/Out 4 (Not implemented at time of publication) Suspend In Suspend, places auto sequencing on hold (active low) 2.8.9.6 Audio Inhibit In Inhibit Audio Messages (active low) 2.8.9.7 RESERVED RESERVED 2-20 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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Installation Procedures Function Connection RSVD CDI / VDI Ground Connection Discrete Discrete Outputs Reserved RSVD Inputs RSVD Audio RSVD Serial SYNCRO VIEW LOOKING AT REAR OF UNIT Figure 2-10 - 78-Pin Connector Detail GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 2-21...
50ma when unit is on 2.8.8.4 Composite Ground return path for the composite signal 2.8.4 (see Figure 2-8 for a diagram of a 37-pin connector) 2-22 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
TO/FROM indications. The CDI key on the bezel of the GNS 480 is used to toggle between the display of GPS and VOR/ILS information on the CDI window and remote CDI. The navigation source is displayed in the CDI window.
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Each flag output provides (V – 2) volts relative to ground when valid information is present, where V represents the aircraft power supplied to the GNS 480. Each output is capable of supplying up to 400 2.8.2.5 OBS Resolver The OBS resolver input should be compatible with a standard 6-wire OBS interface - any electrical zero crossing will work because the GNS 480 will calibrate out any errors.
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Installation Procedures NOTE The GNS 480 cannot drive multiple resolvers at the same time. It is not recommended that external resolvers be switched through a relay or other means because the resolver must be calibrated to the radio. If multiple resolvers are desired in the installation, the primary unit must be installed and calibrated as described herein.
OMPOSITE NDICATOR The GNS 480 provides a standard VOR/localizer composite output signal that may be used to drive the left/right deviation, TO / FROM and valid flag indications of certain navigation indicators that contain an internal converter. If an external converter is driven from the composite output, the composite output will be disabled whenever the VOR monitor mode is active or back course localizer mode is enabled.
GNS 480 front panel. Refer to 2.5.3 to determine whether or not external annunciators are required. All of the annunciator outputs duplicate annunciations available on the front of the GNS 480. These can be used to drive annunciator lamps to make the annunciation available remotely (such as in the pilot’s primary field of view).
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P5-60 Dead Reck Annc The Dead Reck Annc output is grounded whenever the GNS 480 is in dead reckoning mode (i.e. whenever the GPS position is lost and the last-known groundspeed is > 3kts). If an external annunciator is used for dead reckoning annunciation, it is recommended that the dead reckoning annunciator be labeled “DR”...
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WAAS altitude more than (50 meters plus the vertical protection limit (VPL)) below the altitude at the FAF If an external annunciator is used for altitude alert annunciation, it is recommended that the altitude alert annunciator be labeled “ALT” in amber text. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 2-29...
The Precision Appr output is grounded when a precision approach is active. Currently, the precision approach output will be active when the GNS 480 nav radio is tuned to a localizer and the VOR/ILS radio navigation data is selected for display on the CDI. This output may be connected to the ILS Energize input of an autopilot or flight director to provide higher autopilot gain when the GNS 480 is operating in precision approach mode.
GNS 480 front panel. All of the switch inputs duplicate functions available on the front of the GNS 480. These can be used to make the function available remotely.
Audio Inhibit In The Audio Inhibit In is used to inhibit the GNS 480 audio messages. A ground on this input causes GNS 480 audio messages not to be played; if this input is open GNS 480 audio messages will be played. Any audio messages that are inhibited because of this input will not be played when the audio inhibit condition is removed.
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SL30 for display on its front panel. The GNS 480 can communicate with a PDA using the infrared sensor on the front bezel. If this feature is used it must be set up on RxD3 and TxD3, not allowing these lines to be used for communication with other devices.
The GNS 480 can receive air data, heading data, wind data, traffic data and selected course from suitable equipment. The labels that are used by the GNS 480 depend upon the port configuration. Below is a list of available input configurations and the labels accepted by each one: 1.
Magnetic Variation ● ● UTC (Binary) Localizer Deviation [Note 2] ● Glideslope Deviation [Note 3] ● Baro Corrected Altitude ● ● VOR Omnibearing (From aircraft to station) ● Distance To Go ● ● GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 2-35...
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[3] Binary DDM for glideslope deviation is limited to ±0.175. [4] The GNS 480 Equipment Hex ID is 002 for configurations 1, 2, and 5. For configuration 4, the Hex ID is 010 when a localizer is tuned, and 011 when a VOR is tuned.
2.8.12 VHF C The GNS 480 provides an internal COM transceiver that can be interfaced to an audio panel or connected directly to a speaker. The PTT input is used to enable the Com MIC audio and cause the Com transceiver to transmit on the active frequency.
2.8.13 VHF N The GNS 480 provides an internal NAV receiver that can be interfaced to an audio panel. An optional external input is also available to allow the user to toggle the active and standby Nav frequencies. Refer to Appendix D for interconnect information.
2.8.14.2 Audio Inhibit In P5-76 Audio Inhibit In The Audio Inhibit In may be used by higher priority systems to inhibit the GNS 480 audio messages. Refer to section 2.8.9.7 for additional details. 2.8.15 RMI / OBI The GNS 480 RMI/OBI output can be used to drive an RMI (or OBI) navigation indicator. The OBI Select input is used to select the source (GPS or Nav radio) used to provide the bearing.
DME T UNING The GNS 480 can channel a DME based upon the tuned VOR frequency. The GNS 480 outputs the King Serial DME channeling format. When the DME Select input is grounded, the GNS 480 will actively tune the DME.
GPS signals. This can happen when the comm (GNS 480 or any other comm) is transmitting on certain frequencies such as 121.15 or 121.175 MHz, which may cause the ELT output circuit to oscillate from the signal coming in on the ELT antenna coax.
VHF comm transceiver to reduce or eliminate the harmonic interference. A notch filter for this use (part #162-1059) is available from Garmin AT. NOTE GNS 480 performance has been verified in typical installations and has not shown problems of the built-in comm interfering with the GPS when installed according to the recommended installation guidelines.
Most VOR/LOC-only antennas will still provide an adequate glideslope signal for the GNS 480 to operate normally. If two nav receivers (e.g. one GNS 480 and one SL30) are installed in the aircraft, a splitter must be used. Installations should use an appropriate splitter, such as the Mini-Circuits ZFSC-2-1B BNC, available as an option under the Garmin AT part number 115-0007.
Circuits should be protected in accordance with guidelines in AC 43.13-1B, chapter 11, section 2, paragraph 429. Power inputs should be across a minimum of all four specified input pins. Figure 2-12 - GNS 480 Center of Gravity 2-44 560-0982-01 Rev A...
1, 4, and MENU/ENTER in sequence immediately after the GNS 480 initialization is complete and before any other bezel keys on the GNS 480 are pressed. Line select key 1 is the top line select key, line select key 4 is the fourth key down, and MENU/ENTER is the lower most key below the line select keys.
ETUP UNCTION The SETUP function allows the custom configuration of the GNS 480 for each individual installation. The SETUP function allows the installer to configure the serial and ARINC 429 ports, calibrate the resolver head (if installed), calibrate the baro potentiometer (if installed), and set COM parameters.
[3] The CROSSFILL configuration is used to allow GNX 480’s to share information in a dual GNS 480 installation. [4] If SKYWATCH or SKYWATCH NO UI is set up on an ARINC 429 input, the GTX33+TIS option will not be available. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
ALL in the SDI column (the value of ALL cannot be changed). The SDI field on the ARINC 429 outputs can be configured as SYS 1, SYS 2, or ALL. For dual GNS 480 installations, each GNS 480 must have a unique source name (SYS 1 or SYS 2). For a single GNS 480 installation, select ALL.
3. Follow the instructions on the display for calibrating the resolver. If the GNS 480 will not accept the calibration or advances to the next prompt when the MENU/ENTER key is pressed, there may be a problem with the resolver interface.
Figure 3-5 - Resolver Calibration Page The GNS 480 cannot drive multiple resolvers at the same time. It is not recommended that external resolvers be switched through a relay or other means because the resolver must be calibrated to the radio as described in this procedure.
INSTALLED. 2. Follow the instructions on the display for calibrating the baro potentiometer. If the GNS 480 will not accept the calibration when the MENU/ENTER key is pressed, there may be a problem with the baro potentiometer interface.
MISC line select key. Press the CDI SEL line select key to toggle between USE (for installations that will utilize the GNS 480 CDI bezel key to switch between Nav and GPS) or IGNORE (for installations where it is desired that the CDI bezel key be inoperative). If the CDI Select is set to IGNORE, the field beside the CDI key will always be GPS, regardless of CDI key presses.
Figure 3-10 – Measurement of GPS Vertical Offset While on the Ground Maintenance SETUP menu Page 2, press the GPS line select key. The GPS Vertical Offset setup page is shown in Figure 3-11. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
NOTE Refer to the appropriate GTX transponder installation manual for a additional information on the parameters that can be configured via the GNS 480. NOTE If the GNX 480 is not communicating with the GTX transponder, all of the editable fields for the setup items shown in the following sections will be dashed out.
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Post-Installation Configuration & Checkout GTX Main Setup Page for GTX 32/327 GTX Main Setup Page for GTX 33/330 Figure 3-12 - GTX Main Setup Page GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 3-11...
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FADC NO ALT / FADC W/ALT / REMOTE Notes: [1] Only one output setting will be available. The setting that is displayed cannot be changed and depends upon the configuration set up on RS-232 serial port 6. 3-12 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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OFF / GPS / ADC NO ALT / ADC W/ALT / EF/AD NO ALT / EF/AD W/ALT High / Low CH_IN_4 OFF / ADLP High / Low CH_OUT_1 OFF / GARMIN / GARMIN W/TIS / ADLP High / Low CH_OUT_2 OFF / GARMIN / GARMIN W/TIS High / Low GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
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MENU/ENTER key to save the settings. Press the BACK smart key to return to the GTX Main Setup menu. The configuration options for the aircraft configuration items are listed below: 3-14 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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If address is a US registration number, FLT ID can be the same. SAME AS TAIL Enter FLT ID every time the unit is turned on in normal mode. POWER UP ENTRY Enter FLT ID in configuration mode only. CONFIG ENTRY GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 3-15...
Either press the small, inner knob again or press the MENU/ENTER key to save the settings. Press the BACK smart key to return to the GTX Main Setup menu. 3-16 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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Advisory" in TCAS terms). 4 = "Timer Expired,” when the countdown timer expires (this aural message not used in installations with the GNS 480). 5 = "Traffic Not Available,” when TIS service is not available or out of range of an operating TIS Mode S site.
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If Gillham altitude is not being provided to the transponder, INVALID will be displayed. NOTE The GTX 32/327 transponder does not currently support this function, so INVALID will always be displayed, even if the transponder is receiving valid Gillham altitude. 3-18 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
3.3.1.1 Test Function The Test function allows the checkout of the display, controls, and I/O of the GNS 480. While in the Ground Maintenance mode, press the TEST smart key to enter the Test menu, which is shown in the top part of Figure 3-18.
When on the appropriate page turn the large, outer knob to select the flag to be tested. Then turn the small, inner knob to change the setting of that flag. Test each setting for every flag of each CDI connected to the GNS 480. Press the TEST or BACK smart key to return to the Ground Maintenance Test menu.
As a minimum, perform the LEFT, MID and RIGHT tests for the lateral deviation needle of each CDI connected to the GNS 480. Press the TEST or BACK smart key to return to the Ground Maintenance Test menu. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 3-21...
150mV, and 0 corresponding to the center) As a minimum, perform the DOWN, MID and UP tests for the vertical deviation needle of each CDI connected to the GNS 480. NOTE For some HSI’s the glideslope indicator may not be visible unless it is receiving a valid signal from the localizer (ILS Energize is present).
P5-60 For each annunciator that is used, verify proper operation by turning the annunciator ON and OFF. Press the TEST or BACK smart key to return to the Ground Maintenance Test menu. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 3-23...
Post-Installation Configuration & Checkout 3.3.1.1.5 Display Test The Display Test function displays various test patterns and can be used to verify the GNS 480 display operation. While on the Ground Maintenance main TEST menu page, press the NEXT PAGE line select key, followed by the DISPLAY line select key to go to the Display Test page.
Figure 3-25 - Bezel Key Test The bezel key test should be run upon initial installation or any time a problem is suspected with one of the GNS 480 bezel keys or knobs. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A...
Vary the roll/steer value left and right and verify that the autopilot behaves accordingly. Press the TEST or BACK smart key to return to the Ground Maintenance Test menu. 3-26 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
Post-Installation Configuration & Checkout 3.3.1.2 Input Monitor Function The Input Monitor Function monitors the external inputs to the GNS 480 and displays the data currently being received. Press the INPUT smart key in the Ground Maintenance mode to reach the Interface Monitor Function, as shown in Figure 3-27.
Details for each of the inputs that can be monitored are shown in Table 3-6. For each GNS 480 ARINC 429 input that is used, verify that data is being received. If no data is being received, ensure that (i) the source equipment is turned on, (ii) the ARINC 429 input type and speed has been set up correctly, and (iii) the wiring is correct.
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The voltage and frequency of the 26VAC, 400Hz input will 26VAC 26 VAC Reference P5-20,39 be displayed. If this input is not connected, or if the voltage is below 1VAC, ‘---‘ will be displayed. GNS 480 (CNX80) Installation Manual560-0982-01 Rev A 3-29...
3.3.2.1.1 Initial Power-Up The first time the GNS 480 is used after it is installed, the GPS seed position, UTC time and date must be entered. Following the display of the main start-up screen, the screen shown in Figure 3-30 will be displayed for 10 seconds.
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Figure 3-30 – GPS Information Start-up Screen If the exact position is not known, the GNS 480 can determine its own initial position. If it is desired to let the GNS 480 determine its own position, do not enter the position, time and date after the CHG smart key is pressed.
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Ensure that NO POSITION FIX is not displayed. Press the COM bezel key and tune the GNS 480 Com to 121.125 MHz. Listen on the frequency to ensure it is not in use, and then transmit for 30 seconds.
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Press the CDI bezel key to select VOR CDI mode (indicated by a green VOR in the left portion of the GNS 480 CDI display). To the right of the VOR indication is the current setting of the OBS. Verify that the OBS decodes properly from 0 to 360 degrees (the value displayed on the GNS 480 should be within ±2°...
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GNS 480 to the audio panel is functional. Prior to proceeding with this check, ensure that the audio panel is set to annunciate the GNS 480 message audio. If the following steps do not perform correctly, check the electrical connections and AMA volume setting.
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The GNS 480 can receive altitude or fuel/air data from an external source. This check verifies that the GNS 480 is receiving data from these units. Ensure that the GNS 480 and MX20 are turned on and in normal mode. If the following steps do not perform correctly, check the electrical connections and configuration setup.
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1. Check the System Info page on the MX20 to verify that the data is available to each port and that it is being processed properly. 2. Load a flight plan into the GNS 480 and verify that the flight plan is displayed on the MX20 on the FPL page.
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(Baro Correct.). 3. Change the baro correction on GNS 480 #1 and verify that it changes to the same value on GNS 480 #2. Repeat by changing the baro correction on GNS 480 #2 and verifying that it changes to the same value on GNS 480 #1.
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This check verifies that the units are communicating. Ensure that the GNS 480 and SL30 are turned on and in normal mode, and that the GNS 480 has a valid position. If the following steps do not perform correctly, check the electrical connections and configuration setup.
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2. In the GNS 480, set a course to a destination waypoint. This can be done by pressing the NRST bezel key to display a list of nearby waypoints. Then use the large, outer knob to select a suitable waypoint and press the DIRECT-TO bezel key, followed by the Direct line select key.
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1. On the GNS 480 go to the traffic page. This page is accessed by pressing the FN key repeatedly until the TFC smart key is displayed. The TFC smart key is then pressed to display the traffic page.
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If GPS position is lost, a “WARNING Loss of Navigation” message will be displayed. 2. Enter and activate a flight plan on the GNS 480. Fly the flight plan and verify that the display of flight plan data is consistent with the CDI indication (deviation, TO/FROM…) in the pilot’s primary field of view.
Check the database to ensure it is current. The database information is displayed at startup. To check the database: 1. Turn off the GNS 480 and then turn it on. The GNS 480 will go through its normal start-up sequence.
Use Table 4-1 to assist in troubleshooting. Devices connected to the GNS 480, such as an SL30, SL70 or MX20 can be useful for determining whether the GNS 480 is functioning properly or if there are problems with the installation.
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• MX20 software prior to v5.x. • Update MX20 software. • Wiring connections are incorrect. • Check wiring • The GNS 480 is not configured • DST data (Distance, Go to serial port setup page and verify Speed, Time) is not correctly.
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• GNS 480 baro pot input not • Calibrate baro pot altimeter calibrated • GNS 480 is not the only device • Ensure GNS 480 is the only device tied to the altimeter baro pot connected to the altimeter baro pot •...
GNS 480’s controlling the SL70). 480’s controlling the SL70). 4.2 C ONTACTING THE ACTORY FOR SSISTANCE If the GNS 480 unit fails to operate despite troubleshooting efforts, contact Garmin Technical Support for assistance. GARMIN International, Inc. 1200 East 151 Street Olathe, KS 66062-3426...
5.1 O PERATION There are no Part 23 aircraft type limitations. All functions of the GNS 480 meets the appropriate design assurance qualifications for primary or secondary for airplane Class I, Class II, Class III, and Class IV in accordance with AC 23.1309-1C Figure 2. The TSO authorizations with the RTCA/DO178B software levels by function are listed in Table 1-1.
For Aircraft on the AML certified under 14 CFR Part 23 post amendment 41, use of the GNS 480 for IFR operations requires a functional redundant electrical power system. 5.3 A...
IFR flight. Refer to CFR 14 paragraph 91.171. Every 30 days verify the limits of the permissible indicated bearing error. The last VOR check information may be entered into the GNS 480 via the Nav VOR Mode then on the Test Log Menu page.
A.1 E NVIRONMENTAL UALIFICATION The GNS 480 has been tested to the following environmental categories per procedures defined in RTCA/DO-160D. Tests were conducted from September 2002 to April 2003 using the original 1997 revision of DO-160D and specification defined in PD3107.
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Appendix A - Certification Data A.2 GNS 480 STC D Refer to Garmin AT document 560-0988-00 for data regarding GNS 480 STC authorization. This document contains information on the following items: • Supplementary Type Certificate (STC) • STC Permission •...
PECIFICATIONS This appendix includes the RS232 serial port interface specifications. The RS-232 serial interface configurations supported by the GNS 480 are described below. Instructions for configuring the serial port are included in the checkout procedure in section 3.2.1.1. Serial output connections should be limited to a maximum of three external units.
Appendix B - Serial Interface Specifications B.1.1 Altitude Encoder/Converter Input The GNS 480 will accept various serial altitude formats. The only configuration required for the altitude encoder input is the baud rate – the serial altitude format will be recognized automatically. The input signals shall be compatible with RS-232C and have the following characteristics: Baud rate: ..........1200/9600 (defined by encoder used)
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<+/-> sign indicator sensor temperature checksum of bytes 1 through 14 in hex ASCII (e.g., "FA") <CR> carriage return (0x0d) Note: Checksum is calculated by adding each byte in the message (1 through 14). GNS 480 (CNX80) Installation Manual 560-0982-01 Rev A...
The format of the fuel/air data computer input is as follows, which conforms to the Shadin “S” format serial message. Definition of the input message data that the GNS 480 uses is included in Table B- 3. A sample input message is illustrated in Figure B- 2.
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The format of the fuel/air data computer input is as follows, which conforms to the Shadin “Z” format serial message. Definition of the input message data that the GNS 480 uses is included in Table B- 4. Baud rate: ..........9600 Data bits: ..........
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Current Latitude, s = N or S, dd = degrees, mm = minutes sdddmmhh Current Longitude, s = E or W, ddd = degrees, mm = minutes, hh = hundredths of minutes CKSM2 Checksum of labels S to X (0 to 255) 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
(and optional TIS traffic). B.2.1 Mapcom Output When M is selected, the GNS 480 will transmit moving map data, nearest waypoint data, flight APCOM plan waypoints, and nav/com data on this output. The format of the MapCom output is as follows: Baud rate: ..........
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= hundredths of minutes x = undefined Magnetic variation at waypoint nnnnnnnn LS byte (msbit...lsbit) nnnnnnnn MS byte (msbit...lsbit) Two’s complement binary in sixteenths of degrees, easterly variation is positive. <CR> ASCII carriage return (0Dh) GNS 480 (CNX80) Installation Manual 560-0982-01 Rev A...
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‘\r’ Item Terminator <0x0d> B.2.1.3 Flight Plan Waypoint Type Data The following data is only transmitted when preceded by flight plan data. There is one character per flight plan waypoint transmitted. B-10 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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The definition of the NavComm portion of the MapCom data output is as follows. This data output is compatible with the SL30 or SL40 for sending frequency data to the comm or nav unit. The comm data is output using the following format. $PMRRC<msg_id><msg_data><chksum><cr> GNS 480 (CNX80) Installation Manual 560-0982-01 Rev A B-11...
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000 to 975 kHz in 25 kHz steps, or 0 to 39. Example Message $PMRRC0511IT64<cr> The above example message outputs a ground frequency type, 121.900 MHz. B-12 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
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The following two commands work together in allowing the GNS 480 to provide a list of VOR frequencies to a remote device (such as the SL30). The GNS 480 will send a sequence of Remote VOR Input commands (message identifier 20). When all of the VOR Input commands have been sent, the GNS 480 will send a Remote VOR List Trailer command (message identifier 21) to terminate the list.
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There may be up to twenty entries in the remote Localizer list. B.2.1.4.4.1 Remote Localizer List Header This output command marks the beginning of a Localizer list sent by the GNS 480. It specifies the five character airport identifier associated with the localizer frequencies in the list. Message format: “V”....
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Appendix B - Serial Interface Specifications B.2.1.4.6 Distance/Speed/Time Message If an SL30 is connected to the GNS 480, the GNS 480 will send the following message to the SL30. $PMRRV41rrrrssshmm<CHECKSUM><CR><LF> rrrr is the distance to the station in 0.1nm units...
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Appendix B - Serial Interface Specifications OTES B-16 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
[1] If it is desired to have the F/ADC calculate wind data, ground speed and track angle must be provided to the FADC using a GNS 480 MAPCOM RS232 output. If the MAPCOM data is not supplied to the FADC, the GNS 480 will calculate wind data using other data supplied by the FADC.
LTIMETERS FOR ORRECTION The following altimeters are compatible with the GNS 480. Other altimeters may be used to provide baro correction to the GNS 480 provided they have a potentiometer with a minimum resistance of 5 kΩ. Manufacturer Model Notes...
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The following EHSI’s are compatible with the GNS 480. Other EHSI’s or navigation displays may be used with the GNS 480 provided that they accept serial data in the format defined in B.2.1 or ARINC 429 data as defined in 2.8.10.2.2.
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Appendix C - Equipment Compatibility OTES 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...
Aircraft Make and Model Designation Installation Requirements Raytheon (Beech) The GNS 480 must be installed in the manufacturer’s provided avionics stack. E33, E33A, E33C, F33, External CDI/HSI source selection annunciation is required. The CDI/HSI F33A, F33C, G33 source select annunciation must be installed in accordance with 2.5.3.2.
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Appendix E – Acceptable Aircraft by Evaluation OTES 560-0982-01 Rev A GNS 480 (CNX80) Installation Manual...