Becker BXP6401-1 Series, Installation And Operational Manual

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5. Installing the transponder antenna 1A032
A. The transponder antenna has to be fitted (outside) to the bottom of the aircraft
at a horizontal, flat location. This location should not be in the “shadow” of air-
craftstructure items. The highest range is achievied when the antenna is
located at the lowest point of the aircraft fuselage.
B. The installation dimensions of the transponder antenna 1A032 is shown in
Fig. 2-2.
CAUTION :
n
The transponder antenna 1A032 is provided with a silicone rubber
gasket which must also be interposed between the skin of the aircraft
and the antenna.
n
In aircraft having a wooden or plastic airframe an electric counter-
weight plate or panel must be located within the fuselage at the an-
tenna location with minimum dimensions of 40x40 cm (15.7x15.7 inch).
C. Antenna cable
RG-58C/U (0.9 dB/m) or RG-223/U (0.6 dB/m) can be used for the transpon-
der. If the cable length is longer than 2 m between the unit and the antenna,
the cable type RG- 223/U is recommended. The maximum cable length
shouldn’t be more than 5 m. The attenuation loss of the antenna cable must
n’t be higher than 3 dB in complete.
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September 2011
INSTALLATION AND OPERATION BXP6401-X-(XX)