GNC255A/255B Pilot's Guide
Page 9
... 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's Guide vii
... 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's Guide vii
GNC255A/255B Pilot's Guide
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...Station (FSS) Frequencies 3-8 3.2.7 Com Nearest Weather (WX) Frequencies 3-9 3.3 Nav Frequencies 3-10 3.3.1 Recent Nav Frequencies 3-10 3.3.2 Nav User Frequencies 3-11 3.3.2.1 Viewing the Nav User Frequency 3-11 3.3.2.2 Deleting the Nav User Frequency 3-11 3.3.2.3 Editing a Nav User Frequency 3-12 3.3.3 Nav Database Frequencies 3-13 3.3.4 Nav Nearest VOR 3-14 3.4 ICS Configuration 3-15 3.4.1 Adjust Intercom 3-15 3.4.2... 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.
...Station (FSS) Frequencies 3-8 3.2.7 Com Nearest Weather (WX) Frequencies 3-9 3.3 Nav Frequencies 3-10 3.3.1 Recent Nav Frequencies 3-10 3.3.2 Nav User Frequencies 3-11 3.3.2.1 Viewing the Nav User Frequency 3-11 3.3.2.2 Deleting the Nav User Frequency 3-11 3.3.2.3 Editing a Nav User Frequency 3-12 3.3.3 Nav Database Frequencies 3-13 3.3.4 Nav Nearest VOR 3-14 3.4 ICS Configuration 3-15 3.4.1 Adjust Intercom 3-15 3.4.2... 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.
GNC255A/255B Pilot's Guide
Page 13
... to 335 MHz) when the localizer is tuned. 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 available with 200 channel VOR, Localizer and Glideslope receivers, the GNC 255 provides a full-functioned navigation and communications solution in a small...
... to 335 MHz) when the localizer is tuned. 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 available with 200 channel VOR, Localizer and Glideslope receivers, the GNC 255 provides a full-functioned navigation and communications solution in a small...
GNC255A/255B Pilot's Guide
Page 14
..., and bezel keys. 1.2.1 Power/Com Volume/Squelch Knob The Power/Com Volume/Squelch knob located in the upper left of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Rotating the knob clockwise past the detent turns power on and counter-clockwise turns ...Com Volume/Squelch knob to access sophisticated functionality. When Morse code tone is active, "ID" will be heard. 1.2 Pilot Controls The GNC 255 controls have been designed to simplify operation of the system and minimize workload and the time required to toggle automatic squelch control On/Off ...
..., and bezel keys. 1.2.1 Power/Com Volume/Squelch Knob The Power/Com Volume/Squelch knob located in the upper left of the Nav active frequency. 1-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Rotating the knob clockwise past the detent turns power on and counter-clockwise turns ...Com Volume/Squelch knob to access sophisticated functionality. When Morse code tone is active, "ID" will be heard. 1.2 Pilot Controls The GNC 255 controls have been designed to simplify operation of the system and minimize workload and the time required to toggle automatic squelch control On/Off ...
GNC255A/255B Pilot's Guide
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... 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 T/F key does not operate for tuning frequencies and data entry. A Garmin GNC 255A/255B Pilot's Guide 1-3 The OBS...
... 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 T/F key does not operate for tuning frequencies and data entry. A Garmin GNC 255A/255B Pilot's Guide 1-3 The OBS...
GNC255A/255B Pilot's Guide
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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. A Pressing the FUNC key a second time exits the Function mode. 1.2.11 MON (Monitor) Key The MON... Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. 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 once displays the Function mode...
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. A Pressing the FUNC key a second time exits the Function mode. 1.2.11 MON (Monitor) Key The MON... Active frequency. 1.3 USB Port The USB port is used to update the frequency database in the GNC 255. 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 once displays the Function mode...
GNC255A/255B Pilot's Guide
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... to the Active frequency. Turn the LARGE knob to 15 frequencies. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A small "MN" will switch automatically to Nav mode. 2.2.3 Saving a Com Channel The current Standby frequency may be active. 2. The Frequency Monitor function is not affected...
... to the Active frequency. Turn the LARGE knob to 15 frequencies. After selecting the desired characters, press ENT. 2-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. A small "MN" will switch automatically to Nav mode. 2.2.3 Saving a Com Channel The current Standby frequency may be active. 2. The Frequency Monitor function is not affected...
GNC255A/255B Pilot's Guide
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...Turn the SMALL Knob To Select Frequency Type Figure 2-7 Database Waypoint Type Selection 4. Waypoint Types with a "+" sign will be remembered for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. 2.2.4 Com Database Look-Up 1. Waypoint Types with a "+" ...scroll through the list of waypoint types. 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 the CURSOR knob from the Com display to activate the database look-up function...
...Turn the SMALL Knob To Select Frequency Type Figure 2-7 Database Waypoint Type Selection 4. Waypoint Types with a "+" sign will be remembered for Com and Nav frequencies that are in the database when the unit is receiving a valid position input. 2.2.4 Com Database Look-Up 1. Waypoint Types with a "+" ...scroll through the list of waypoint types. 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 the CURSOR knob from the Com display to activate the database look-up function...
GNC255A/255B Pilot's Guide
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.... Press ENT. After selecting the 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. Press and release the FLIP/FLOP key to...
.... Press ENT. After selecting the 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. Press and release the FLIP/FLOP key to...
GNC255A/255B Pilot's Guide
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... Landing System 01-36 Runway Heading Blank None Table 2-2 - Turn the LARGE knob to the left of the active Nav frequency. When Nav ident is enabled, the ID annunciation will appear to move the cursor. A Garmin GNC 255A/255B Pilot's Guide 2-7 Nav Frequency Type List 2.3.3 Listening to decrease volume. 190-01182-01 Rev. Turn the...
... Landing System 01-36 Runway Heading Blank None Table 2-2 - Turn the LARGE knob to the left of the active Nav frequency. When Nav ident is enabled, the ID annunciation will appear to move the cursor. A Garmin GNC 255A/255B Pilot's Guide 2-7 Nav Frequency Type List 2.3.3 Listening to decrease volume. 190-01182-01 Rev. Turn the...
GNC255A/255B Pilot's Guide
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...bar to change the displayed OBS values. 2.4 OBS Mode If your remote display will be on the screen of the GNC 255. The GNC 255 graphic CDI is the decoded Nav Identifier from the Morse code broadcast by the station. 1. A Each dot indicates two degrees deflection with an external CDI... full deflection to see the current OBS setting and graphic CDI. 2. 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. NOTE: The Identifier is ...
...bar to change the displayed OBS values. 2.4 OBS Mode If your remote display will be on the screen of the GNC 255. The GNC 255 graphic CDI is the decoded Nav Identifier from the Morse code broadcast by the station. 1. A Each dot indicates two degrees deflection with an external CDI... full deflection to see the current OBS setting and graphic CDI. 2. 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. NOTE: The Identifier is ...
GNC255A/255B Pilot's Guide
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...Bearing To/From Station Active Nav Frequency Distance To Station In Nautical Miles Time To Station In Hours and Minutes Ground Speed From GPS Unit In Knots Figure 2-15 DST Data Display NOTE: The If both GPS and DME data sources are connected to the GNC and dashes are not connected... data is not shown, pressing the T/F key will show DST data in the lower part of the display. A Garmin GNC 255A/255B Pilot's Guide 2-9 2.5 Distance/Speed/Time (DST) Display When the GNC 255 has received data from an external device, such as a GPS receiver or DME sensor through the serial port, DST ...
...Bearing To/From Station Active Nav Frequency Distance To Station In Nautical Miles Time To Station In Hours and Minutes Ground Speed From GPS Unit In Knots Figure 2-15 DST Data Display NOTE: The If both GPS and DME data sources are connected to the GNC and dashes are not connected... data is not shown, pressing the T/F key will show DST data in the lower part of the display. A Garmin GNC 255A/255B Pilot's Guide 2-9 2.5 Distance/Speed/Time (DST) Display When the GNC 255 has received data from an external device, such as a GPS receiver or DME sensor through the serial port, DST ...
GNC255A/255B Pilot's Guide
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... 3-1 Functions Diagram 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot's Guide 3-1 Start/Stop CLR - Accept Count Up ENT - 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 Freqs User Freqs Database Nearest Apt...
... 3-1 Functions Diagram 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot's Guide 3-1 Start/Stop CLR - Accept Count Up ENT - 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 Freqs User Freqs Database Nearest Apt...
GNC255A/255B Pilot's Guide
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... 3-2 Recent Com Frequencies 3. Press the ENT key to transfer the displayed channel to access the Functions. 2. A Press the FUNC key to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. NOTE: When switching from 8.33 kHz to access the function. 5. This only affects the user frequencies within... SMALL knob to the Active frequency position. Turn the LARGE knob to view the Recent frequency function. 1. Turn the SMALL knob to select the COM, NAV, ICS, or SYS functions. 3. Turn the LARGE knob to view the choices in this function.
... 3-2 Recent Com Frequencies 3. Press the ENT key to transfer the displayed channel to access the Functions. 2. A Press the FUNC key to the Standby frequency position. 3-2 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. NOTE: When switching from 8.33 kHz to access the function. 5. This only affects the user frequencies within... SMALL knob to the Active frequency position. Turn the LARGE knob to view the Recent frequency function. 1. Turn the SMALL knob to select the COM, NAV, ICS, or SYS functions. 3. Turn the LARGE knob to view the choices in this function.
GNC255A/255B Pilot's Guide
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... access the Functions. Turn SMALL Knob To Select Entry. Press FLIP/FLOP Key To Set Selected Freq As Active Selected Frequency Figure 3-15 Recent Nav Frequencies 2. A 3.3 Nav Frequencies The Nav Frequencies category in the Functions section contains remotely acquired frequencies (Remote), recently used frequencies (Recent), user-defined frequencies (User), and a database of... the displayed channel to the Active frequency position or press the ENT key to transfer the displayed channel to the Standby frequency position. 3-10 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev.
... access the Functions. Turn SMALL Knob To Select Entry. Press FLIP/FLOP Key To Set Selected Freq As Active Selected Frequency Figure 3-15 Recent Nav Frequencies 2. A 3.3 Nav Frequencies The Nav Frequencies category in the Functions section contains remotely acquired frequencies (Remote), recently used frequencies (Recent), user-defined frequencies (User), and a database of... the displayed channel to the Active frequency position or press the ENT key to transfer the displayed channel to the Standby frequency position. 3-10 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev.
GNC255A/255B Pilot's Guide
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... Selected Freq As Standby Active Frequency Position In List. While viewing a Nav User frequency, press the CLR key to select the Nav Frequency List Function. Press the ENT key to view the Nav User Frequency function. A Garmin GNC 255A/255B Pilot's Guide 3-11 Turn the SMALL knob to delete the... displayed frequency. 190-01182-01 Rev. Deleting the Nav User Frequency 1. Press FLIP/FLOP Key...
... Selected Freq As Standby Active Frequency Position In List. While viewing a Nav User frequency, press the CLR key to select the Nav Frequency List Function. Press the ENT key to view the Nav User Frequency function. A Garmin GNC 255A/255B Pilot's Guide 3-11 Turn the SMALL knob to delete the... displayed frequency. 190-01182-01 Rev. Deleting the Nav User Frequency 1. Press FLIP/FLOP Key...
GNC255A/255B Pilot's Guide
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.... Turn the SMALL knob to select characters and Turn the LARGE knob to move the cursor and then turn the SMALL knob to select the Nav User Frequencies. After selecting the desired characters, press ENT. 5. Turn the LARGE knob to select the WPT name.Turn the SMALL knob to select characters... SMALL knob to select the kHz frequency value. 3. A Press FUNC. The frequency MHz value will be selected. After selecting the desired characters, press ENT. 3-12 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev.
.... Turn the SMALL knob to select characters and Turn the LARGE knob to move the cursor and then turn the SMALL knob to select the Nav User Frequencies. After selecting the desired characters, press ENT. 5. Turn the LARGE knob to select the WPT name.Turn the SMALL knob to select characters... SMALL knob to select the kHz frequency value. 3. A Press FUNC. The frequency MHz value will be selected. After selecting the desired characters, press ENT. 3-12 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev.
GNC255A/255B Pilot's Guide
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...then press the ENT key. 5. Turn the SMALL knob to view the Nav Database function. Press the ENT key to set the selected frequency as the Standby frequency. 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot's Guide 3-13 Press ENT Key To Set Selected Freq...key to access the Functions. With the Nav Frequency Function highlighted, turn the SMALL knob to select the desired character. If available, the Frequency Type will be recalled by identifier. 1. 3.3.3 Nav Database Frequencies The GNC 255 contains a large database of Nav frequencies that may be highlighted. Press FUNC...
...then press the ENT key. 5. Turn the SMALL knob to view the Nav Database function. Press the ENT key to set the selected frequency as the Standby frequency. 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot's Guide 3-13 Press ENT Key To Set Selected Freq...key to access the Functions. With the Nav Frequency Function highlighted, turn the SMALL knob to select the desired character. If available, the Frequency Type will be recalled by identifier. 1. 3.3.3 Nav Database Frequencies The GNC 255 contains a large database of Nav frequencies that may be highlighted. Press FUNC...
GNC255A/255B Pilot's Guide
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... Press the CLR Key To Return the Displayed Value to view the Nav Nearest VOR function. Press FUNC to select the desired identifier and then press ENT and continue as the standby or active frequency. A Then, press ENT. 3-14 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Turn the SMALL knob... Selected Frequency Press FLIP/FLOP Key To Set Selected Identifier Selected Freq As Active Wpt Type Figure 3-25 Set Selected Frequency as Active or Standby 3.3.4 Nav Nearest VOR The GNC 255, when interfaced with an appropriate GPS receiver, will report the 25 nearest VORs.
... Press the CLR Key To Return the Displayed Value to view the Nav Nearest VOR function. Press FUNC to select the desired identifier and then press ENT and continue as the standby or active frequency. A Then, press ENT. 3-14 Garmin GNC 255A/255B Pilot's Guide 190-01182-01 Rev. Turn the SMALL knob... Selected Frequency Press FLIP/FLOP Key To Set Selected Identifier Selected Freq As Active Wpt Type Figure 3-25 Set Selected Frequency as Active or Standby 3.3.4 Nav Nearest VOR The GNC 255, when interfaced with an appropriate GPS receiver, will report the 25 nearest VORs.
GNC255A/255B Pilot's Guide
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... to adjust the intercom, set the Nav/Aux volume, turn the Intercom On/Off, and turn the intercom speaker On/Off. 3.4.1 Adjust Intercom The Adjust Intercom function allows you to set values for the Intercom squelch and volume. Turn the SMALL knob to set the value. A Garmin GNC 255A/255B Pilot's Guide 3-15...
... to adjust the intercom, set the Nav/Aux volume, turn the Intercom On/Off, and turn the intercom speaker On/Off. 3.4.1 Adjust Intercom The Adjust Intercom function allows you to set values for the Intercom squelch and volume. Turn the SMALL knob to set the value. A Garmin GNC 255A/255B Pilot's Guide 3-15...