FSG 70/FSG 71M
O
PERATION
M
ANUAL
Reprint July 1998
Page
3 - 7
W. Dittel GmbH
3.3.3 Antenna Installation
A conventional 50 Ohm vertically polarized COM antenna is required with the
FSG 70/FSG 71M
transceivers. The antenna must be able to radiate equally distributed
RF energy without interference.
For installation in an aircraft with a metal fuselage, we recommend our AV-529
antenna (part No. ZT 037), for wooden and plastic aircraft, our swiveling aviation
communications antenna with four aluminum ground plane strips (ZT 008) and for
aircraft with vertical tail rudder of non-conductive material (Notice: carbon fiber is
conductive and screens the antenna), our folded top antenna (to be installed in vertical
rudder during rudder manufacturing. Installation drawing available on request.).
The location for the antenna must be carefully selected, and the installation
instructions must be followed exactly if optimal results are to be expected.
•
The antenna should be mounted vertically on or under the fuselage such that it is
well removed from any projections that may shield RX and TX such as propeller/s,
landing gear or rudders.
•
The distance to other antennas, e.g., COM, NAV, etc. should be at least 1.5 meter.
If two units of FSG 50, FSG 60/60 M, 70/71M are used, a distance of one meter is
sufficient.
•
The area of installation should be flat as far as possible around the antenna.
•
The metal-to-metal contact between the aircraft's surface and the antenna must be
very good. For aircraft with non-metallic surfaces, metal foil (80 x 80 cm, min.) is to
be glued to the interior of the fuselage or four crossed strips of sheet metal are to
be installed (see above: aviation communications antenna with aluminum ground
plane). The ground plane must be bolted directly at the foot of the antenna
(conductive connection).
•
With thin fuselage skin, the mounting hole must be suitably reinforced. All breaches
of the exterior skin are to be carefully closed with sealant. This step may not
degrade the electric contact.
•
When routing the antenna cable, sharp bends and unnecessary length are to be
avoided.
•
Installation of a folded-top antenna in the vertical tail rudder is to be made by the
aircraft's manufacturer.
