Alternate Display of Antenna Dynamics
The following alternate format prints several derived parameters related to the dynamic properties of each antenna axis. One axis is displayed at a time. The azimuth axis printout is shown below. The alternate display for the elevation axis is identical.
AZ–Pos AzTach AzDrv T–Cal/Vel/Ratio T–Dot T–Err I–Mom Time
–––––– –––––– ––––– –––––––––––––––––––– –––––– ––––– ––––– ––––
359.95 –11.67 –2.3 –13.72 –3.25 1.013 2.86 –1.0 2.81 5.29The displayed values are:
AZ-Pos- Pedestal position angle in degrees (°).
AzTach- The represents the Pedestal tachometer levels, scaled to -100 ... +100 T-Units.
AzDrv- Pedestal drive signals, scaled to -100 ... +100 D-Units.
T-Cal / Vel / Ratio- The tachometer calibration values consist of a one-second averaged tachometer calibration level (T-units) and a computed actual velocity based on various positions (°/s). Both numbers define the map from the tachometer T-units to velocities (°/s). The slope ratio, implied by the current values to the stored slope from the axis menu, is displayed. This ratio should be close to 1.000 for all rates of rotation. The antenna must be in motion for these values to be valid.
T-Dot / T-Err / I-Mom- The time derivative of the tachometer (that is the acceleration) is displayed in T-units/sec followed by the extrapolated tachometer error in T-units, based on a 2.5-second integration of an internal antenna model. This tachometer error is the basis of an unresponsive antenna check that is continually executed in the background. The antenna's instantaneous moment of inertia is displayed in D-units and T-units/sec. The antenna must be accelerating for these values to be valid.
Time- The seconds counter increments from 0 ... 10 with 0.01-second resolution. These values are included for measuring the elapsed time between display lines.