GNC255A/255B Pilot's Guide
Page 9
... 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...
... 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...
GNC255A/255B Pilot's Guide
Page 10
... 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...
... 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...
GNC255A/255B Pilot's Guide
Page 13
... paired frequencies (328 MHz to 136.975 MHz, in memory, builtin course deviation indicator, and more. The GNC 255's Com radio operates in 10 and 16 watt com transmitter versions. A Garmin GNC 255A/255B Pilot's Guide 1-1 Besides traditional Nav/Com features, the GNC 255 also incorporates workload-reducing functions such as automatic decoding of 8.33 kHz steps is tuned. The...
... paired frequencies (328 MHz to 136.975 MHz, in memory, builtin course deviation indicator, and more. The GNC 255's Com radio operates in 10 and 16 watt com transmitter versions. A Garmin GNC 255A/255B Pilot's Guide 1-1 Besides traditional Nav/Com features, the GNC 255 also incorporates workload-reducing functions such as automatic decoding of 8.33 kHz steps is tuned. The...
GNC255A/255B Pilot's Guide
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... dual concentric knobs for frequency tuning, Com volume/squelch knob, Nav volume/ID knob, and bezel keys. 1.2.1 Power/Com Volume/Squelch Knob The Power/Com Volume/Squelch knob located in the bottom left of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-...01 Rev. This facilitates listening to reject many localized noise sources. Press the Power/Com Volume/Squelch knob again to return to access sophisticated functionality. 1.2 Pilot Controls The GNC 255 controls have...
... dual concentric knobs for frequency tuning, Com volume/squelch knob, Nav volume/ID knob, and bezel keys. 1.2.1 Power/Com Volume/Squelch Knob The Power/Com Volume/Squelch knob located in the bottom left of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-...01 Rev. This facilitates listening to reject many localized noise sources. Press the Power/Com Volume/Squelch knob again to return to access sophisticated functionality. 1.2 Pilot Controls The GNC 255 controls have...
GNC255A/255B Pilot's Guide
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... or radial FROM the active VOR. A Garmin GNC 255A/255B Pilot's Guide 1-3 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. Switching between Com frequencies is installed with an external converter. 1.2.7 T/F...
... or radial FROM the active VOR. A Garmin GNC 255A/255B Pilot's Guide 1-3 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. Switching between Com frequencies is installed with an external converter. 1.2.7 T/F...
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. Pressing the FUNC key a second time exits the Function mode. 1.2.11 MON (Monitor) Key The ... the Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. 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 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. Pressing the FUNC key a second time exits the Function mode. 1.2.11 MON (Monitor) Key The ... the Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. 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 once displays the Function mode. ...
GNC255A/255B Pilot's Guide
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...affected. The Com User Frequency database can hold up to Nav mode. 2.2.3 Saving a Com Channel The current Standby frequency may be saved into the Com User Frequency database from the Com display or the Com User Function. A Press the MON key in the Com function to listen...Monitoring the Standby Com Channel The Frequency Monitoring function allows you to monitor the Standby frequency for activity, while listening to select characters. 3. NOTE: When switching from the user frequency list. Press ENT. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B ...
...affected. The Com User Frequency database can hold up to Nav mode. 2.2.3 Saving a Com Channel The current Standby frequency may be saved into the Com User Frequency database from the Com display or the Com User Function. A Press the MON key in the Com function to listen...Monitoring the Standby Com Channel The Frequency Monitoring function allows you to monitor the Standby frequency for activity, while listening to select characters. 3. NOTE: When switching from the user frequency list. Press ENT. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B ...
GNC255A/255B Pilot's Guide
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... frequencies for Selection 2. 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. Waypoint Types with a "+" sign will have more frequencies for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. Selected Identifier...
... frequencies for Selection 2. 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. Waypoint Types with a "+" sign will have more frequencies for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. Selected Identifier...
GNC255A/255B Pilot's Guide
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...For The Selected Frequency Figure 2-10 Nav Frequency Selection CAUTION: The Identifier is determined from the Nav or the Nav User Function. Turn the LARGE knob to reach the Nav radio function. After selecting the desired characters, press ENT. 2-6 Garmin GNC 255A/255B Pilot's Guide 190-...field will show. 2. The NAV annunciator on the top line of Nav frequencies is not the decoded Nav Identifier. 4. Turn the SMALL knob to the Active frequency. 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...
...For The Selected Frequency Figure 2-10 Nav Frequency Selection CAUTION: The Identifier is determined from the Nav or the Nav User Function. Turn the LARGE knob to reach the Nav radio function. After selecting the desired characters, press ENT. 2-6 Garmin GNC 255A/255B Pilot's Guide 190-...field will show. 2. The NAV annunciator on the top line of Nav frequencies is not the decoded Nav Identifier. 4. Turn the SMALL knob to the Active frequency. 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...
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. Fly towards the bar 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. Fly towards the bar to see the current...
GNC255A/255B Pilot's Guide
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A Garmin GNC 255A/255B Pilot's Guide 3-1 Settings ENT - 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 Freqs User Freqs Database Nearest Apt Nearest ACC Nearest FSS Nearest WX Recent Freqs User Freqs Database...
A Garmin GNC 255A/255B Pilot's Guide 3-1 Settings ENT - 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 Freqs User Freqs Database Nearest Apt Nearest ACC Nearest FSS Nearest WX Recent Freqs User Freqs Database...
GNC255A/255B Pilot's Guide
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.... Turn the LARGE knob to access the function. 5. Press and release the FLIP/FLOP key to transfer the displayed channel to select the COM, NAV, ICS, or SYS functions. 3. Then, press ENT. 2. Turn the LARGE knob to the Active frequency position. Turn SMALL Knob To Select Entry Selected Frequency Press ... list. Press the ENT key to transfer the displayed channel to view the Recent frequency function. Turn the SMALL knob to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Press FUNC to access the Functions.
.... Turn the LARGE knob to access the function. 5. Press and release the FLIP/FLOP key to transfer the displayed channel to select the COM, NAV, ICS, or SYS functions. 3. Then, press ENT. 2. Turn the LARGE knob to the Active frequency position. Turn SMALL Knob To Select Entry Selected Frequency Press ... list. Press the ENT key to transfer the displayed channel to view the Recent frequency function. Turn the SMALL knob to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Press FUNC to access the Functions.
GNC255A/255B Pilot's Guide
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...Is Used With The flyGarmin Services 2. Press the FUNC key to return to access the Functions. Press FUNC to the main menu. 3-22 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Turn the LARGE knob to select the SYS Function. Turn the LARGE knob to select ...the database is useful when contacting Customer Support. 1. Display Software Version Com Software Version Nav Software Version Figure 3-39 Software Versions Display 2. Turn the SMALL knob to the main menu. 3.5.7 Serial Number The serial number of the GNC 255 unit are displayed. Press the FUNC key to return to view ...
...Is Used With The flyGarmin Services 2. Press the FUNC key to return to access the Functions. Press FUNC to the main menu. 3-22 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Turn the LARGE knob to select the SYS Function. Turn the LARGE knob to select ...the database is useful when contacting Customer Support. 1. Display Software Version Com Software Version Nav Software Version Figure 3-39 Software Versions Display 2. Turn the SMALL knob to the main menu. 3.5.7 Serial Number The serial number of the GNC 255 unit are displayed. Press the FUNC key to return to view ...
GNC255A/255B Pilot's Guide
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... Time Value Press ENT to Accept Press CLR to Return Turn LARGE Knob To Move Cursor the Selected Value to Start or Stop the timer. A Garmin GNC 255A/255B Pilot's Guide 3-23 Now, press the ENT key. Press the ENT key to the Default Value Figure 3-43 Setting the Count Down Timer... to Reset the Timer or Stop the Timer to access the Functions. 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 Com/Nav displays. Press FUNC to the Default Value Figure 3-42 Selecting the Count Down Timer 3. Turn...
... Time Value Press ENT to Accept Press CLR to Return Turn LARGE Knob To Move Cursor the Selected Value to Start or Stop the timer. A Garmin GNC 255A/255B Pilot's Guide 3-23 Now, press the ENT key. Press the ENT key to the Default Value Figure 3-43 Setting the Count Down Timer... to Reset the Timer or Stop the Timer to access the Functions. 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 Com/Nav displays. Press FUNC to the Default Value Figure 3-42 Selecting the Count Down Timer 3. Turn...
GNC255A/255B Pilot's Guide
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... via the menu. Contact dealer Recalibrate resolver 4-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. If the condition persists, contact dealer. A No voice activation, or if must talk too loud Com Radio not communicating. 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...
... via the menu. Contact dealer Recalibrate resolver 4-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. If the condition persists, contact dealer. A No voice activation, or if must talk too loud Com Radio not communicating. 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...
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