Digital Tracking Positioners

       Data Takeoff Accuracy - the space difference between the
       actual position (measured by optical device) and the position
       displayed on controller screen (under no load). 

       Orthogonality Error - deviation of the elevation axis from true
       perpendicularity with the azimuth axis. 

       Compliance - the inverse spring constant of a structure, bearing,
       drive train, etc.; The compliance is used to determine both
       mechanical resonant frequencies and angular errors introduced
       by external torques. 

       Power Gearing Backlash -  the free angular motion of the
       output member with the input locked.

16. Definitions of applicable parameters are as follows:

15. Pedestal details, shown in the applicable drawings, are for
       reference only and shall be specified for each order, separately.   

14. A dry air-pressurizer unit, electrically operated, is available upon
      request. 

13. A Local Control Unit (LCU) is available as an option. 

12. Electrical Power Requirements: 
       AC input voltage: 3 phase, 208V/60Hz or 380V/50Hz. 

11. The base riser provides the necessary clearance for a 3-meter
       antenna dish assembly. 

10. This pedestal series include a standard elevation bracket. Special
      side-arms, counterweights and antenna mounting tables can be
      designed and provided according to specified user's requirements. 

9. Standard environmental conditions: 
    Operating temperature -20^oC to +50^oC; relative humidity:
    up to 95% including condensation;
    withstands salt atmosphere in coastal regions;
    withstands insects and fungi in tropical regions;
    altitude range 0 to 10,000 ft. 
    Other environmental conditions are available according to specific
    user's requirements. 

8. Standard pedestal color is gloss-white. Other colors are available
    as an option. 

7. The stow provisions consist of manually-interlocked stow-lock pins
    for azimuth and elevation axes. Elevation stowing at position 0^o
    is optionally available. 

6. RF Rotary-Joint assemblies are available in azimuth and elevation
    axes. 

5. Slip-ring assembly enables continuous rotation for azimuth axis.
    When Slip-Ring and Rotary-Joint are used, the limit switches are
    disabled.

4. Models, which are equipped with electrical limit switches, are
    adjustable to specified ranges.
    For limited azimuth travel, a cable-wrap with sector switches is
    available. Elevation axis uses shock absorbing mechanical stops as
    a backup to the electrical limits.

3. Angular velocity and acceleration can be modified according to user's
    requirement.

2. This data is for a dual-drive option on both axes. In addition to our
    standard pedestals, special pedestals are available for applications
    with unique requirements. The pedestals are designed for operation
    with ORBIT antenna controllers, indoor AL-4726-3TC or outdoor
    AL-5005-3T.

1. The pedestal is designed for high dynamic tracking and supported by
    Computer Simulation programs, which enable ORBIT to predict, before
    construction, the overall Pedestal System (Pedestal + Payload) static
    and dynamic performance.