SkyView System Installation Guide - Dynon Avionics

SV-ADSB-470 Installation, Configuration, and Testingaccomplish, but is more difficult in a composite or fabric skinned aircraft. In these cases ametallic ground plane should be fabricated and fitted under the antenna.As the ground plane is made smaller, the actual dimensions of the ground plane become morecritical, and small multiples of the wavelength should be avoided, as should circles. Rectanglesor squares are much less likely to create a critical dimension that resonates with thetransmissions. The smallest practical ground plane is a square around 130 mm per side; as thesize increases the performance may actually get worse, but will be better by the time theground plane is 780 mm on each side. Anything much larger than that size is unlikely to showsignificant further improvement.The thickness of the material used to construct the ground plane is not critical, providing it issufficiently conductive. A variety of proprietary mesh and grid solutions are available.Heavyweight cooking foil meets the technical requirements, but obviously needs to be properlysupported.Antenna CableAn acceptable cable:Has less than 3.0 dB loss for the run length needed. For runs less than 17 feet, RG58is acceptable.Has a characteristic impedance of 50 OhmsIf running the antenna cable in a bundle with or in close proximity to thetransponder antenna cable:o Has double braid screens or has a foil and braid screen. For runs less than 17feet, RG400 is acceptable.When routing the cable, ensure that you:Route the cable away from sources of heat.Route the cable away from potential interference sources such as ignition wiring, 400Hzgenerators, fluorescent lighting and electric motors.Keep the cable run as short as possible.Avoid routing the cable round tight bends.Avoid kinking the cable even temporarily during installation.Secure the cable so that it cannot interfere with other systems.Antenna BNC ConnectorThis section describes the technique for attaching the antenna cable to a BNC connector. A BNCconnector is not supplied with the SV-ADSB-470. The SV-ADSB-470 has a female BNCconnection. Therefore, you will need to source a male BNC connector that is compatible withthe antenna cable type that meets your aircraft’s needs.SkyView System Installation Guide - Revision O 14-7