Honeywell International Inc. KTR2280 Manuale Utente

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 KTR 2280 Preliminary H 08/17/06
Rev. 0, Aug/2006   
©Honeywell International Inc. Do not print without express permission of Honeywell
Page 2-4
It is recommended that a COM be connected to the top antenna for good ground 
communication and that the other COM be connected to the bottom antenna to provide 
good airborne communications.  If mounting antennas on the same side of the aircraft is 
unavoidable, maintain the minimum allowable separation (8 feet).
The antenna should be mounted on a section of the aircraft that is horizontal during cruise 
flight. The base of the antenna should be well bonded to the metal aircraft skin. Remove 
any paint from around the mounting holes to ensure a good connection between the 
antenna and the skin. The metal aircraft skin at the base of the antenna should extend a 
minimum of twenty-four inches in every direction. This provides the ground plane required 
for the antenna. Any less metallized area will result in reduced communication range at 
some bearings around the aircraft and may increase interference to and from other 
systems.
The COM transceiver performance depends heavily on the integrity of the electrical 
bonding to the airframe and also the electrical integrity of the aircraft structure. If the 
electrical resistance between an antenna and the aircraft or between adjacent skin panels 
change intermittently, noisy communications may result.
Connect the antenna to the COM unit with 50 ohm coaxial cable, keeping the cable length 
to a minimum and avoiding sharp bends in the cable. Keep the COM antenna cable as far 
away from other antenna cables as possible and do not bundle several cables together.
Use Dow-Corning DC-4, or equivalent, on both inside and outside of the connector and 
its mate as an effective barrier against moisture and to prevent corrosion.
2.3.4.2 NAVIGATION ANTENNAS
The NAV antenna should be well removed from other antennas, projections, engines or 
propellers. It should have a clear line of sight area if possible. The antenna must be 
mounted symmetrically with the center line of the aircraft. Avoid running other coaxial 
cables and wires near the NAV antenna cable.
The VOR/LOC antenna with Glideslope is a two piece dipole with one part mounted on 
each side of the vertical stabilizer. It should be installed on the upper section of the vertical 
stabilizer of single finned aircraft and be at least 28 inches (measured vertically) from the 
horizontal stabilizer.
On dual VOR/ILS installations, it is recommended that a splitter be used to divide signals 
from a single VOR/LOC antenna into two or more receivers. Use double shielded cables 
to reduce interference to the receivers.