Garmin GNS 480 Installation Manaul

Also see for Apollo CNX80: User Newsletter User Newsletter Supplemental Flight manual Pilot's guide Data list

Contents

Installation ProceduresGNS 480 (CNX80) Installation Manual 560-0982-01 Rev L 2-45NOTEGNS 480 performance has been verified in typical installations and has not shownproblems of the built-in COM interfering with the GPS when installed according to therecommended installation guidelines.If a VHF COM transmitter causes problems with the GPS on the selected frequencies as listed in the post-installation checkout, the problem may be due to the ELT. This can be verified by disconnecting the ELTantenna coax at the ELT unit. If the ELT is found to cause the problem, then contact the ELTmanufacturer or replace the ELT.Figure 2-12 - Rear Coax Connector Assembly2.9.3 NAV AntennaThe NAV antenna is a standard 50Ω horizontally polarized NAV/VOR/Localizer/Glideslope antenna thatreceives VOR frequencies between 108 and 117.95 MHz, and localizer frequencies between 108 and 112MHz, and glideslope information between 328.6 and 335.4 MHz. Follow the antenna manufacturer’sinstallation instructions for mounting antennas. The NAV antenna should be mounted as far apart aspractical from the ELT antenna. It is recommended that the installer use RG-142B or equivalent 50Ω coaxfor the NAV antenna.The GNS 480 incorporates an internal diplexor circuit. This means that the input VHF signal must notstrip the glideslope (330 MHz) signal from the NAV (108 MHz) signal. Do not install an externaldiplexor. It is recommended that a single VOR/Localizer/Glideslope antenna be used for the installation.Most VOR/LOC-only antennas will still provide an adequate glideslope signal for the GNS 480 to operatenormally.If two nav receivers (e.g. one GNS 480 and one SL30) are installed in the aircraft, a splitter must be used.Installations should use an appropriate splitter, such as the Mini-Circuits ZFSC-2-1B BNC, available as anoption under the Garmin AT part number 115-0007.2.10 Weight and BalanceWeight and balance computation is required after the installation of the GNS 480. Follow the guidelines as