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GNC 255A/255B
Pilot’s Guide
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© 2012 Garmin Ltd. or its subsidiaries. All rights reserved. This manual reflects the operation of System Software version 2.00, or later. Some differences in operation may be observed when comparing the information in this manual to later software versions. Garmin International, Inc., 1200 East 151st Street, Olathe, KS 66062, U.S.A. Tel: 913/397.8200 Fax: 913/397.8282 Garmin AT, Inc., 2345 Turner Road SE, Salem, OR 97302, U.S.A. Tel: 503/391.3411 Fax 503/364.2138 Garmin (Europe) Ltd.,
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LIMITED WARRANTY All Garmin avionics products are warranted to be free from defects in materials or workmanship for: two years from the date of purchase for new Remote-Mount and Panel-Mount products; one year from the date of purchase for new portable products and any purchased newly-overhauled products; six months for newly-overhauled products exchanged through a Garmin Authorized Service Center; and 90 days for factory repaired or newly-overhauled products exchanged at Garmin in lieu of re
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WARNING: For safety reasons, GNC 255 operational procedures must be learned on the ground. CAUTION: The Garmin GNC 255 does not contain any user-serviceable parts. Repairs should only be made by an authorized Garmin service center. Unauthorized repairs or modifications could void both the warranty and the pilot’s authority to operate this device under FAA/FCC regulations. CAUTION: The GNC 255 display uses a lens coated with a special anti- reflective coating that is very sensitive t
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NOTE: Canadian installations: In accordance with Canadian Radio Specifications Standard 102 (RSS 102), RF field strength exposure to persons from an antenna connected to this device should be limited to 60 V/m for controlled environment and 28 V/m for uncontrolled environment. 190-01182-01 Rev. A iii Garmin GNC 255A/255B Pilot’s Guide
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NOTE: This device complies with Part 15 of To obtain accessories for your unit, please the FCC limits for Class B digital devices. This contact your Garmin dealer. equipment generates, uses, and can radiate radio frequency energy and, if not installed Help us better support you by completing our and used in accordance with the instructions, on-line registration form today! Registration may cause harmful interference to radio ensures that you will be notified of product communications. Fur
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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. If you have any questions, the Garmin Product Support department may be reached Monday through Friday, 7:00 AM to 7:00 PM Central
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Record of Revisions Part Number Revision Date Description 190-01182-01 A 11/19/12 Initial release vi 190-01182-01 Rev. A Garmin GNC 255A/255B Pilot’s Guide
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Contents Product Registration and Support ......................................................................v 1 Getting Started ....................................................................................1-1 1.1 Product Description ..............................................................................1-1 1.2 Pilot Controls .......................................................................................1-2 1.2.1 Power/Com Volume/Squelch Knob ............................
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3 Functions ..............................................................................................3-1 3.1 Functions Description ...........................................................................3-1 3.2 Com Frequencies .................................................................................3-2 3.2.1 Recent Com Frequencies ........................................................3-2 3.2.2 Com User Frequencies ...........................................................3-3 3
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3.6.3 Viewing Timers in the Com Display .......................................3-24 4 Appendix ..............................................................................................4-1 4.1 Troubleshooting ...................................................................................4-1 4.2 Updating the Frequency Database ........................................................4-3 4.2.1 Downloading the Frequency Database ...................................4-3 4.2.2 Updating the GNC 2
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1 GETTING STARTED 1.1 Product Description Combining a powerful VHF communications transceiver with 200 channel VOR, Localizer and Glideslope receivers, the GNC 255 provides a full-functioned navigation and communications solution in a small footprint at a very affordable price. Besides traditional Nav/Com features, the GNC 255 also incorporates workload-reducing functions such as automatic decoding of the Morse code station identifier for VOR/LOC, most-used frequency storage in memory, buil
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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 access sophisticated functionality. Controls are comprised of 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 top left corner of the bezel controls audio volume for the Com radio. Rotating the knob clockwise p
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1.2.3 Tuning LARGE/SMALL Concentric (Cursor) Knobs The LARGE right and SMALL right knobs are used for tuning frequencies and data entry. LARGE, Outer Knob SMALL, Inner Knob 1.2.4 FLIP/FLOP Key Press and release the FLIP/FLOP key to switch between the active (left-most) and standby (right-most) frequency. Switching between Com frequencies is disabled while you 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 Pres
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1.2.10 FUNC (Function) Key The FUNC (Function) key accesses function categories for the following: the Com Radio, Nav Radio, ICS Configuration, System Configuration, and Timer. Pressing the FUNC key once displays the Function mode. Pressing the FUNC key a second time exits the Function mode. 1.2.11 MON (Monitor) Key The MON (Monitor) key will engage the monitor function where the Standby frequency may be monitored while still listening to the Active frequency. 1.3 USB Port The USB po
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2 BASIC OPERATION 2.1 Power On Turn the GNC 255 on by either turning the Power/Com Volume/ Squelch knob clockwise to turn the power on or, if installed, turning on the master switch that powers the radios. 2.2 Com Radio 2.2.1 Selecting a Com Frequency 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 GNC 255 to select the de
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2.2.2 Monitoring the Standby Com Channel The Frequency Monitoring function allows you to monitor the Standby frequency for activity, while listening to the Active frequency. Press the MON key in the Com function to listen to the standby frequency. A small “MN” will replace the “STB” to the left of the Standby frequency. Monitor Annunciation Standby Frequency Being Monitored Figure 2-2 Com Frequency Monitor Annunciation When the Active frequency receives a signal, the unit will switch
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5. Turn the LARGE knob to select the waypoint Type. 6. Turn the SMALL knob to select the Type from the list. Selected Wpt Type Figure 2-4 Com User Frequency Type Selection Frequency Type Symbol Description TWR Tower GND Ground ATIS Automatic Terminal Information Service AWS Automated Weather Observing System ATF Aerodrome Traffic Frequency ARR Arrival APPR Approach DEP Departure CLR Clearance CTAF Common Traffic Advisory Frequency FSS Flight Service Station RFS Remote Flight Service Stati
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2.2.4 Com Database Look-Up 1. Press the CURSOR knob from the Com display to activate the database look-up function. Identifier Field Active for Selection Turn SMALL Knob To Select Character Turn LARGE Knob To Move Cursor Figure 2-5 Database Identifier Active for Selection 2. Turn the SMALL knob to select characters and turn the LARGE knob to move the cursor. Selected Identifier Figure 2-6 Database Identifier Selection 3. After selecting the desired characters, press ENT. Turn the
