COBHAM EXPLORER 7100GX, Installation And User Manual, Page: 13 / 78

Description of the system components
98-147366-A Chapter 2: Introduction 2-3
Introd
ucti
on
2.2 Description of the system components
2.2.1 Antenna positioner
The auto-deploy antenna positioner can accommodate -4° to 86° of angular movement in
the elevation axis and ± 200° in the azimuth axis. The mechanical assemblies rely on two
independent axes to allow for precise antenna pointing. A ground gradient of up to 8° can
be accommodated with the terminal’s levelling features. The antenna positioner can stay
outside in rainy weather.
Cable drive system
The cable drive system uses highly reliable aircraft control cables in a redundant
configuration to achieve a lightweight, very stiff drive system with zero backlash. This high-
tech performance is achieved using low-tech components, by simply wrapping the cable
around the drive capstan several times before wrapping the larger drive drum. This method
results in a minimum free-length of cable. The load cable on the main drum is exponentially
reduced as it is wrapped around the drum. Therefore, the total elongation of the cable
under load is minimized. The system has up to 10 times less backlash than that of
comparable gear systems. The cables are pre-tensioned and spring-loaded at the main drum
attachment point, which eliminates backlash at installation and from any unexpected cable
stretch in the future.
Figure 2-3: EXPLORER 7100GX antenna with antenna positioner
Antenna
positioner