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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 personal...
(iv) damage caused by service performed by anyone who is not an authorized service provider of Garmin; or (v) damage to a product that has been modified or altered without the written permission of Garmin. In addition, Garmin reserves the right to refuse warranty claims against products or services that are obtained and/or used in contravention of the laws of any country.
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Unauthorized repairs or modifications could void both the warranty and the pilot’s authority to operate this device under FAA/FCC regulations. CAUTION: The GTR 225 display uses a lens coated with a special anti- reflective coating that is very sensitive to skin oils, waxes, and abrasive cleaners.
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Please, have the serial particular installation. number of your unit handy, connect to our web site (www.garmin.com) and look for our If this equipment does cause harmful Product Registration link on the Home page. interference, the user is encouraged to try...
Product Registration and Support Help us better support you by completing your online registration today! Have the serial number of your product handy and connect to the Garmin web site (www.garmin.com or https://fly.garmin.com/fly-garmin). Look for the Product Registration link on the Home page. Also, be sure to record your serial number in the space provided.
Recent Com Frequencies ............3-2 3.2.2 Com User Frequencies ............3-3 3.2.2.1 Viewing the Com User Frequency ........... 3-3 3.2.2.2 Deleting the Com User Frequency .......... 3-3 3.2.2.3 Editing a Com User Frequency ..........3-4 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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Appendix ....................4-1 Troubleshooting ................... 4-1 Updating the Frequency Database ............4-3 4.2.1 Downloading the Frequency Database ........4-3 4.2.2 Updating the GTR 225 Frequency Database ......4-3 Messages .................... 4-4 Index .....................Index-1 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
The GTR 225 series has the ability to monitor the standby Com frequencies. The GTR 225 (10 watt) Com radio operates in the aviation voice band, from 118.000 to 136.975 MHz, in 25 kHz steps (default). For European operations, the additional Com radio configuration of 8.33 kHz steps is provided with the...
Pilot Controls The GTR 225 controls have been designed to simplify operation of the system and minimize workload and the time required to access sophisticated functionality. Controls are comprised of dual concentric knobs for frequency tuning, Com volume/squelch knob, and bezel keys.
Pressing the CLR key erases information, cancels entries, and resets timers. 1.2.8 ENT (Enter) Key Press the ENT key to save selected values, to confirm a prompt, or to save the Standby frequency. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Standby frequency may be monitored while still listening to the Active frequency. USB Port The USB port is used to update the frequency database in the GTR 225. NOTE: Garmin recommends the use of a USB 2.0 compatible USB flash drive for updating the database.
New frequencies are first selected as a Standby frequency and then toggled to the Active side with the FLIP/FLOP key. While viewing the Standby frequency display, use the LARGE and SMALL knobs on the right side of the GTR 225 to select the desired frequency.
Press the ENT Key to Save Press the CLR Key To Revert Move Cursor the Displayed Value to the Previous Value Figure 2-3 Com User Frequency Name Selection 4. After selecting the desired characters, press ENT. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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Clearance CTAF Common Traffic Advisory Frequency Flight Service Station Remote Flight Service Station Mandatory Frequency Unicom Blank None Table 2-1 - Com Frequency Type List 7. After making a selection, press ENT. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
(COM RMT XFR) key for approximately two seconds. I Figure 2-8 Emergency Channel 2. The Emergency Channel will be inserted into the Active Frequency position and the previous Active Frequency will become the Standby Frequency. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
The GTR 225 helps protect you from a situation where the microphone may get stuck in the ON or Transmit position. If the microphone is keyed for longer than 35 seconds, the GTR 225 will return to the receive mode on the selected frequency.
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This page intentionally left blank 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Software Ver Serial Number Timers Count Up ENT - Start/Stop CLR - Reset Count Down ENT - Start/Stop CLR - Reset Push CRSR - Settings ENT - Accept Figure 3-1 Functions Diagram 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Figure 3-2 Recent Com Frequencies 3. Press and release the FLIP/FLOP key to transfer the displayed channel to the Active frequency position. Press the ENT key to transfer the displayed channel to the Standby frequency position. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Press ENT Key To Delete Selected Freq Position In List. Active Frequency Turn SMALL Knob To Select Entry. Selected Frequency Press ENT To Confirm Deleting The Selected Freq Figure 3-4 Deleting User Com Frequencies 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
6. Turn the SMALL knob to select the Waypoint Type. Select Wpt Type Figure 3-8 Com User Frequency Type Selection 7. After selecting the Waypoint Type, press ENT to accept changes to the User Frequency. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
3.2.3 Com Database Frequencies The GTR 225 contains a large database of Com frequencies that may be recalled by identifier. Turn SMALL Knob To Select Character Turn LARGE Knob To Move Cursor Figure 3-9 Com Database Frequencies 1. Press FUNC to access the Functions. With the Com Frequency Function highlighted, turn the SMALL knob to view the Com Database function.
3.2.4 Com Nearest Airports (APT) The GTR 225 will report the 25 nearest Airports (APT), when interfaced with an appropriate GPS receiver. Turn SMALL Knob To Scroll Through Available Airports Figure 3-11 Com Nearest APT Frequencies 1. Press FUNC to access the Functions. With the Com Frequency Function highlighted, turn the SMALL knob to view the Com Nearest APT function.
Active frequency. 3.2.6 Com Nearest Flight Service Station (FSS) Frequencies The GTR 225, when interfaced with an appropriate GPS receiver, will report the 25 nearest Flight Service Station (FSS) frequencies. Turn SMALL Knob To Scroll Through Available Frequencies Figure 3-13 Com Nearest FSS Frequencies 1.
3.2.7 Com Nearest Weather (WX) Frequencies The GTR 225, when interfaced with an appropriate GPS receiver, will report the 25 nearest Weather (WX) frequencies. Turn SMALL Knob To Scroll Through Available Frequencies Figure 3-14 Com Nearest Weather Frequencies 1. Press FUNC to access the Functions. With the Com Frequency Function highlighted, turn the SMALL knob to view the Com Nearest Weather function.
Figure 3-16 Adjust the Intercom Values 3. Turn the LARGE knob to select the ICS Squelch or Volume. Turn the SMALL knob to set the value. Then, press the ENT key to save the selected values. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Previous Value Figure 3-18 Adjust the Aux Audio 4. Press the CLR key to revert to the previous Volume value and then repeat step 3 to select a new value. 3-10 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Selected Value Figure 3-20 Turn the Speaker On/Off 2. Turn the SMALL knob to set the speaker output On or Off. Then, press the ENT key to save the selected value. 3-11 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Press CLR to Return the Selected Value to the Previous Value Figure 3-21 Com Spacing Display 2. Turn the SMALL knob to set the Com spacing and then press the ENT key. 3-12 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
3.4.2 Display Brightness As it arrives from the factory, the GTR 225 automatically adjusts its display brightness for the current lighting conditions. A small sensor on the display is used for this function. A manual adjustment is available for controlling the brightness level of the display as an offset from the “normal”...
3.4.4 Database Info The Database information for the GTR 225 unit is displayed. This information is useful when contacting Customer Support. 1. Press FUNC to access the Functions. Turn the LARGE knob to select the SYS Function. Turn the SMALL knob to view the Database Version function.
3.4.5 Load Database The GTR 225 has a USB connector to allow for easily updating the system databases. NOTE: Garmin recommends the use of a USB 2.0 compatible USB flash drive for updating the database. 1. Insert the supplied cable into the USB port on the top right corner of the GTR 225.
6. Verify the correct frequency database is loaded after power-up. 3.4.6 Software Version The software versions of the GTR 225 unit are displayed. This information is useful when contacting Customer Support. 1. Press FUNC to access the Functions. Turn the LARGE knob to select the SYS Function.
Timers The GTR 225 has both Count Up and Count Down timers, which may operate simultaneously and are shown in the lower right of the Com displays. The countdown timer always takes precedence if it is running. 3.5.1 Setting Up the Count Down Timer 1.
1. Pressing CLR and then ENT will reset the displayed Timer. Figure 3-35 Stop or Clear the Timer in the Com Display 2. Pressing ENT twice will stop the displayed Timer. 3-18 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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Count Up value. The Count Down Timer that is counting up will be highlighted. A Count Up Timer will continue counting separately. Count Down Timer Value Highlighted When Counting Up Figure 3-36 Count Down Timer Value Now Counting Up 3-19 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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This page intentionally left blank 3-20 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Aviation Products Customer Service Department 1200 East 151st Street Olathe, KS 66062-3426 USA If you have any questions, the Garmin AT Product Support department may be reached Monday through Friday, 7:00 AM to 7:00 PM Central Time. US: 913-397-8200 US Toll Free: 1-866-739-5687 Canada Toll Free: 1-866-429-9296 e-mail: support.gat@garmin.com.
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Problem Possible Cause Action GTR 225 does not power on No power to the Check power connections, GTR 225 breakers, and main avionics switch Faulty electrical Contact your dealer to wiring or connection perform electrical system test GTR 225 does not transmit...
The GTR 225 uses a standard USB memory device to load the frequency database into the GTR 225. The memory device is not provided by Garmin. The Frequency database is stored internally and the USB memory device is only used to transfer the database into the unit.
121.5 MHz. Hold 121.5. To exit this mode, hold the remote com com remote transfer (COM RMT transfer key to exit. XFR) switch for two seconds. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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Com remote been in pressed transfer key is position for at least 30 stuck. seconds. This input will now be ignored. This input is not available in all installations. 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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30 seconds. stuck. This input will now be ignored. This input is not available in all installations. Table 4-2 Messages 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
Saving a com channel 2-2 FLIP/FLOP key 1-3 Serial Number 3-16 fly.garmin iv, 3-16, 4-1, 4-3 Software version 3-16 Frequency monitoring 2-2 Speaker On/Off 3-11 Front panel description 1-1 Squelch 1-2 FSS 3-7 Index-1 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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Stuck mic 2-5 Support iv System configuration 3-12 Timers 3-17 Troubleshooting 4-1, 4-4 Updating frequency database 4-3 USB 1-4, 3-15 User frequencies 3-3 Warranty i Index-2 190-01182-00 Rev. A Garmin GTR 225/225A/225B Pilot’s Guide...
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