GNC255A/255B Pilot's Guide
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... 2-1 2.1 Power On 2-1 2.2 Com Radio 2-1 2.2.1 Selecting a Com Frequency 2-1 2.2.2 Monitoring the Standby Com Channel 2-2 2.2.3 Saving a Com Channel 2-2 2.2.4 Com Database Look-Up 2-4 2.2.5 Frequency Database Reverse Look-Up 2-4 2.2.6 Emergency Channel 2-5 2.2.7 Stuck Mic 2-5 2.2.8 Remote Frequency Selection Control 2-5 2.3 Nav Radio 2-6 2.3.1 Selecting a Nav Frequency 2-6 2.3.2 Saving a Nav Channel 2-6 2.3.3 Listening to the Nav Audio Channel 2-7 2.4 OBS Mode 2-8 2.5 Distance/Speed/Time (DST) Display 2-9 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot...
... 2-1 2.1 Power On 2-1 2.2 Com Radio 2-1 2.2.1 Selecting a Com Frequency 2-1 2.2.2 Monitoring the Standby Com Channel 2-2 2.2.3 Saving a Com Channel 2-2 2.2.4 Com Database Look-Up 2-4 2.2.5 Frequency Database Reverse Look-Up 2-4 2.2.6 Emergency Channel 2-5 2.2.7 Stuck Mic 2-5 2.2.8 Remote Frequency Selection Control 2-5 2.3 Nav Radio 2-6 2.3.1 Selecting a Nav Frequency 2-6 2.3.2 Saving a Nav Channel 2-6 2.3.3 Listening to the Nav Audio Channel 2-7 2.4 OBS Mode 2-8 2.5 Distance/Speed/Time (DST) Display 2-9 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot...
GNC255A/255B Pilot's Guide
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... On/Off 3-17 3.5 System Configuration 3-18 3.5.1 Com Spacing 3-18 3.5.2 Display Brightness 3-19 3.5.3 Display Contrast 3-20 3.5.4 Database Info 3-20 3.5.5 Load Database 3-21 3.5.6 Software Version 3-22 3.5.7 Serial Number 3-22 3.6 Timers 3-23 3.6.1 Setting Up the Count Down Timer 3-23 3.6.2 Setting Up the Count Up Timer 3-24 viii Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A
... On/Off 3-17 3.5 System Configuration 3-18 3.5.1 Com Spacing 3-18 3.5.2 Display Brightness 3-19 3.5.3 Display Contrast 3-20 3.5.4 Database Info 3-20 3.5.5 Load Database 3-21 3.5.6 Software Version 3-22 3.5.7 Serial Number 3-22 3.6 Timers 3-23 3.6.1 Setting Up the Count Down Timer 3-23 3.6.2 Setting Up the Count Up Timer 3-24 viii Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A
GNC255A/255B Pilot's Guide
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... GNC 255's Com radio operates in a small footprint at a very affordable price. A Garmin GNC 255A/255B Pilot's Guide 1-1 The GNC 255B is available with a 16 watt com transmitter. The GNC 255A is available with a 10 watt com transmitter. The GNC 255 has the ability to 117.95 MHz decoding both the VHF Omni Range and Localizer navigation signals. Besides traditional Nav/Com features, the GNC 255 also...
... GNC 255's Com radio operates in a small footprint at a very affordable price. A Garmin GNC 255A/255B Pilot's Guide 1-1 The GNC 255B is available with a 16 watt com transmitter. The GNC 255A is available with a 10 watt com transmitter. The GNC 255 has the ability to 117.95 MHz decoding both the VHF Omni Range and Localizer navigation signals. Besides traditional Nav/Com features, the GNC 255 also...
GNC255A/255B Pilot's Guide
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...active, "ID" will be heard. 1.2 Pilot Controls The GNC 255 controls have been designed to simplify operation of the bezel controls audio volume for the Com radio. When the Com radio is overridden. 1.2.2 Nav Volume/ID Knob The Nav Volume/ID knob located in the top left corner of ... active, press the Power/Com Volume/Squelch knob to the left corner of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A You may override the squelch function by pressing the Power/Com Volume/Squelch knob. Press the Power/Com Volume/Squelch knob again to...
...active, "ID" will be heard. 1.2 Pilot Controls The GNC 255 controls have been designed to simplify operation of the bezel controls audio volume for the Com radio. When the Com radio is overridden. 1.2.2 Nav Volume/ID Knob The Nav Volume/ID knob located in the top left corner of ... active, press the Power/Com Volume/Squelch knob to the left corner of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A You may override the squelch function by pressing the Power/Com Volume/Squelch knob. Press the Power/Com Volume/Squelch knob again to...
GNC255A/255B Pilot's Guide
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...data entry. 1.2.3 Tuning LARGE/SMALL Concentric (Cursor) Knobs The LARGE right and SMALL right knobs are transmitting. 1.2.5 C/N (Com/Nav) Key Press the C/N key to select the Com or Nav (VLOC) radio mode. 1.2.6 OBS Key Press the OBS key to see the current OBS setting and graphic CDI. The...key to save selected values, to confirm a prompt, or to switch between the active (left-most) and standby (right-most) frequency. A Garmin GNC 255A/255B Pilot's Guide 1-3 Switching between the bearing TO or radial FROM the active VOR. LARGE, Outer Knob SMALL, Inner Knob 1.2.4 FLIP/FLOP ...
...data entry. 1.2.3 Tuning LARGE/SMALL Concentric (Cursor) Knobs The LARGE right and SMALL right knobs are transmitting. 1.2.5 C/N (Com/Nav) Key Press the C/N key to select the Com or Nav (VLOC) radio mode. 1.2.6 OBS Key Press the OBS key to see the current OBS setting and graphic CDI. The...key to save selected values, to confirm a prompt, or to switch between the active (left-most) and standby (right-most) frequency. A Garmin GNC 255A/255B Pilot's Guide 1-3 Switching between the bearing TO or radial FROM the active VOR. LARGE, Outer Knob SMALL, Inner Knob 1.2.4 FLIP/FLOP ...
GNC255A/255B Pilot's Guide
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...1.2.10 FUNC (Function) Key The FUNC (Function) key accesses function categories for updating the database. 1-4 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A NOTE: Garmin recommends the use of a USB 2.0 compatible USB flash drive for the following: the Com Radio, Nav Radio, ICS Configuration, System Configuration, and Timer. Pressing the FUNC key a second time exits... may be monitored while still listening to the Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. Pressing the FUNC key once displays the Function mode.
...1.2.10 FUNC (Function) Key The FUNC (Function) key accesses function categories for updating the database. 1-4 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A NOTE: Garmin recommends the use of a USB 2.0 compatible USB flash drive for the following: the Com Radio, Nav Radio, ICS Configuration, System Configuration, and Timer. Pressing the FUNC key a second time exits... may be monitored while still listening to the Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. Pressing the FUNC key once displays the Function mode.
GNC255A/255B Pilot's Guide
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...to the Active frequency. Number of the Standby frequency. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. The Com User Frequency database can hold up to move the cursor. Turn the LARGE knob to 15 frequencies. A... Figure 2-2 Com Frequency Monitor Annunciation When the Active frequency receives a signal, the unit will be active. 2. Monitoring is turned off by switching to select characters. 3. The Standby frequency is not affected. Turn the SMALL knob to Nav mode. 2.2.3 Saving a Com Channel The current...
...to the Active frequency. Number of the Standby frequency. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. The Com User Frequency database can hold up to move the cursor. Turn the LARGE knob to 15 frequencies. A... Figure 2-2 Com Frequency Monitor Annunciation When the Active frequency receives a signal, the unit will be active. 2. Monitoring is turned off by switching to select characters. 3. The Standby frequency is not affected. Turn the SMALL knob to Nav mode. 2.2.3 Saving a Com Channel The current...
GNC255A/255B Pilot's Guide
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After selection, the selected waypoint and type will have more frequencies for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. A Selected Identifier Figure 2-6 Database Identifier Selection 3. Waypoint ...Move Cursor Figure 2-5 Database Identifier Active for 30 minutes. Airport Identifier Shown For Freqs In Database Figure 2-8 Frequency Database Reverse Look-Up 2-4 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Press and release the FLIP/FLOP key to swap the Active and Standby frequencies. 2.2.5 Frequency Database...
After selection, the selected waypoint and type will have more frequencies for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. A Selected Identifier Figure 2-6 Database Identifier Selection 3. Waypoint ...Move Cursor Figure 2-5 Database Identifier Active for 30 minutes. Airport Identifier Shown For Freqs In Database Figure 2-8 Frequency Database Reverse Look-Up 2-4 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Press and release the FLIP/FLOP key to swap the Active and Standby frequencies. 2.2.5 Frequency Database...
GNC255A/255B Pilot's Guide
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...desired characters, press ENT. 2-6 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. 2.3 Nav Radio 2.3.1 Selecting a Nav Frequency The selection of the display will be saved into the Nav User Frequency database from the database and is not the decoded Nav Identifier. 4. Turn the LARGE ...Type Shown For The Selected Frequency Figure 2-10 Nav Frequency Selection CAUTION: The Identifier is determined from the Nav or the Nav User Function. NOTE: Both Nav and Com frequencies cannot be displayed at the same time. 2.3.2 Saving a Nav Channel The current Standby frequency may be active. ...
...desired characters, press ENT. 2-6 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. 2.3 Nav Radio 2.3.1 Selecting a Nav Frequency The selection of the display will be saved into the Nav User Frequency database from the database and is not the decoded Nav Identifier. 4. Turn the LARGE ...Type Shown For The Selected Frequency Figure 2-10 Nav Frequency Selection CAUTION: The Identifier is determined from the Nav or the Nav User Function. NOTE: Both Nav and Com frequencies cannot be displayed at the same time. 2.3.2 Saving a Nav Channel The current Standby frequency may be active. ...
GNC255A/255B Pilot's Guide
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NOTE: The Identifier is shown as a graph of five dots right or left of the GNC 255. Active Nav Frequency Identifier Reference Com Frequency OBS Setting To/From Indication for Selected Station CDI Deflection Figure 2-14 CDI Display 2-8 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Use the LARGE and SMALL knobs to see the current...
NOTE: The Identifier is shown as a graph of five dots right or left of the GNC 255. Active Nav Frequency Identifier Reference Com Frequency OBS Setting To/From Indication for Selected Station CDI Deflection Figure 2-14 CDI Display 2-8 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Use the LARGE and SMALL knobs to see the current...
GNC255A/255B Pilot's Guide
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Accept Count Up ENT - A Garmin GNC 255A/255B Pilot's Guide 3-1 Settings ENT - Reset Figure 3-1 Functions Diagram 190-01182-01 Rev. Reset Push CRSR - Start/Stop CLR - 3 FUNCTIONS The Functions section allows provides information about Com Frequencies, Nav Frequencies, Internal Communications System (ICS) Configuration, System Configuration (SYS), and Timers (TMR). 3.1 Functions Description Com Freq Nav Freq ICS Config Recent...
Accept Count Up ENT - A Garmin GNC 255A/255B Pilot's Guide 3-1 Settings ENT - Reset Figure 3-1 Functions Diagram 190-01182-01 Rev. Reset Push CRSR - Start/Stop CLR - 3 FUNCTIONS The Functions section allows provides information about Com Frequencies, Nav Frequencies, Internal Communications System (ICS) Configuration, System Configuration (SYS), and Timers (TMR). 3.1 Functions Description Com Freq Nav Freq ICS Config Recent...
GNC255A/255B Pilot's Guide
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...Frequency Press To Make the Selected Frequency The Active Frequency Press ENT to select the COM, NAV, ICS, or SYS functions. 3. Turn the LARGE knob to Make the Selected Frequency the Standby Figure 3-2 Recent Com Frequencies 3. NOTE: When switching from 8.33 kHz to view the choices in this ... to transfer the displayed channel to select the Com Function. Turn the SMALL knob to 25 kHz mode, any 8.33 kHzspecific user frequencies will be accessed in each function. 4. Turn the LARGE knob to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. ...
...Frequency Press To Make the Selected Frequency The Active Frequency Press ENT to select the COM, NAV, ICS, or SYS functions. 3. Turn the LARGE knob to Make the Selected Frequency the Standby Figure 3-2 Recent Com Frequencies 3. NOTE: When switching from 8.33 kHz to view the choices in this ... to transfer the displayed channel to select the Com Function. Turn the SMALL knob to 25 kHz mode, any 8.33 kHzspecific user frequencies will be accessed in each function. 4. Turn the LARGE knob to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. ...
GNC255A/255B Pilot's Guide
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...GNC 255 unit are displayed. Press the FUNC key to return to view the Software Version function. This information is useful when contacting Customer Support. 1. A Verify the correct frequency database is complete and then remove the memory device and cable. Turn the SMALL knob to the main menu. 3-22 Garmin GNC 255A... access the Functions. Wait until the updating process is loaded after power-up. 3.5.6 Software Version The software versions of the GNC 255 unit is updated. 6. The unit will reset automatically once the database is displayed. Turn the LARGE knob to access the...
...GNC 255 unit are displayed. Press the FUNC key to return to view the Software Version function. This information is useful when contacting Customer Support. 1. A Verify the correct frequency database is complete and then remove the memory device and cable. Turn the SMALL knob to the main menu. 3-22 Garmin GNC 255A... access the Functions. Wait until the updating process is loaded after power-up. 3.5.6 Software Version The software versions of the GNC 255 unit is updated. 6. The unit will reset automatically once the database is displayed. Turn the LARGE knob to access the...
GNC255A/255B Pilot's Guide
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... Press ENT to Accept Press CLR to Return Turn LARGE Knob To Move Cursor the Selected Value to select either the Count Down Timer function. A Garmin GNC 255A/255B Pilot's Guide 3-23 Turn the SMALL knob to the Default Value Figure 3-43 Setting the Count Down Timer Value 190-01182-01 Rev. Press... ENT key. Press ENT again to move the cursor. Press the CURSOR knob to the starting timer value. Now, press the ENT key. 3.6 Timers The GNC 255 has both Count Up and Count Down timers, which may operate simultaneously and are shown in the lower right of the...
... Press ENT to Accept Press CLR to Return Turn LARGE Knob To Move Cursor the Selected Value to select either the Count Down Timer function. A Garmin GNC 255A/255B Pilot's Guide 3-23 Turn the SMALL knob to the Default Value Figure 3-43 Setting the Count Down Timer Value 190-01182-01 Rev. Press... ENT key. Press ENT again to move the cursor. Press the CURSOR knob to the starting timer value. Now, press the ENT key. 3.6 Timers The GNC 255 has both Count Up and Count Down timers, which may operate simultaneously and are shown in the lower right of the...
GNC255A/255B Pilot's Guide
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... remote mounted switch or via the menu. Problem GNC 255 does not power on No Nav audio Nav audio in Com GNC 255 does not transmit Intercom doesn't function Can't change active frequency OBS readout displays "---" Possible Cause No power to the GNC 255 Faulty electrical wiring or connection Output disabled or set... On/Off, Adjust Intercom If in lockout mode. A Contact dealer Recalibrate resolver 4-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. No voice activation, or if must talk too loud Com Radio not communicating. The radio may also be in Lock Out mode, press the ...
... remote mounted switch or via the menu. Problem GNC 255 does not power on No Nav audio Nav audio in Com GNC 255 does not transmit Intercom doesn't function Can't change active frequency OBS readout displays "---" Possible Cause No power to the GNC 255 Faulty electrical wiring or connection Output disabled or set... On/Off, Adjust Intercom If in lockout mode. A Contact dealer Recalibrate resolver 4-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. No voice activation, or if must talk too loud Com Radio not communicating. The radio may also be in Lock Out mode, press the ...
GNC255A/255B Pilot's Guide
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A Garmin GNC 255A/255B Pilot's Guide Index-1 INDEX A Appendix 4-1 B Basic operation 2-1 Brightness 3-19 C Cautions ii, 2-6 Clear 1-3 Com database frequencies 3-5, 3-6, 3-7, 3-8, 3-9 Com frequencies 3-2 Com PTT 3-18 Com radio 2-1 Com;Select frequency 2-1 Com spacing 3-18 Com user frequencies 3-3 Com volume 1-2 Contrast 3-20 Controls 1-2 Cursor 1-3 Customer service i, 4-1 D Database frequencies 3-5, 3-13, 4-3 Database look-up 2-4 Display brightness 3-19 DST 2-9 Duplicate identifiers 3-14 E Emergency channel 2-5 Enter 1-3 F Flight Service ...
A Garmin GNC 255A/255B Pilot's Guide Index-1 INDEX A Appendix 4-1 B Basic operation 2-1 Brightness 3-19 C Cautions ii, 2-6 Clear 1-3 Com database frequencies 3-5, 3-6, 3-7, 3-8, 3-9 Com frequencies 3-2 Com PTT 3-18 Com radio 2-1 Com;Select frequency 2-1 Com spacing 3-18 Com user frequencies 3-3 Com volume 1-2 Contrast 3-20 Controls 1-2 Cursor 1-3 Customer service i, 4-1 D Database frequencies 3-5, 3-13, 4-3 Database look-up 2-4 Display brightness 3-19 DST 2-9 Duplicate identifiers 3-14 E Emergency channel 2-5 Enter 1-3 F Flight Service ...
GNC255A/255B Pilot's Guide
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R Recent com frequencies 3-2 Recent nav frequencies 3-10 Record of Revisions vi Registration v Remote frequency control 2-5 Reverse look-up 2-4 Revisions vi S Saving a com channel 2-2 Saving a nav channel 2-6 Serial Number 3-22 Software version 3-22 Speaker On/Off 3-17 Squelch 1-2 Stuck mic 2-5 Support v System configuration 3-18 T Timers 3-23 To-From 1-3 Troubleshooting 4-1, 4-4 U Updating frequency database 4-3 USB 1-4, 3-21 User frequencies 3-3, 3-11 V Volume 1-2 W Warranty i Index-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A
R Recent com frequencies 3-2 Recent nav frequencies 3-10 Record of Revisions vi Registration v Remote frequency control 2-5 Reverse look-up 2-4 Revisions vi S Saving a com channel 2-2 Saving a nav channel 2-6 Serial Number 3-22 Software version 3-22 Speaker On/Off 3-17 Squelch 1-2 Stuck mic 2-5 Support v System configuration 3-18 T Timers 3-23 To-From 1-3 Troubleshooting 4-1, 4-4 U Updating frequency database 4-3 USB 1-4, 3-21 User frequencies 3-3, 3-11 V Volume 1-2 W Warranty i Index-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A