> For the complete documentation index, see [llms.txt](https://wiki.kscucf.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.kscucf.org/projects/ground-stations/physics-ground-station/calibration.md).

# Antenna Rotator Calibration

This procedure requires at least one person in the lab with access to the rotator controller and at least one person on the PSB roof. Both groups must maintain active communication throughout the procedure.

## Tools

Confirm the required tools to adjust the mounting pole before roof access.

## Calibration procedure

1. Use the rotator controller down arrow to set the rotator altitude/elevation to `0` degrees.
2. Confirm the antennas on the mount bar are parallel with the horizon.
3. If the antennas are not horizontal, loosen and rotate the mounting bar until they are horizontal, then retighten the bar.
4. Use the rotator controller left or right arrows to turn the rotator to true north, which is `0` degrees azimuth.
5. Reset the controller:
   * Turn the controller unit off.
   * Hold the `F` button down.
   * Turn the controller back on while holding `F`.
   * Confirm the display shows `0.0, 0.0`.
6. At this point, the azimuth is calibrated.
7. Use the controller down arrow to move the rotator to full downward travel, which should be approximately `-21.0`.
8. If the rotator stops and the display does not show approximately `-21.0`, the mechanical stop in the rotator has been triggered.
9. Reset the controller again using the reset process above.
10. Use the controller down arrow to move the rotator to full downward travel again.
11. Repeat the full-downward-travel and reset process until there is no more travel.
12. Use the controller up arrow to move the rotator up to the `10` degree mark.
13. Reset the controller again.
14. Test for a full `180` degrees of travel using the controller up arrow.
15. If the travel is approximately `180` degrees or more, setup is correct.
16. If the travel is not approximately `180` degrees or more, repeat the downward-travel and reset process until the travel is correct.

## Maintenance note

Apply WD-40 maintenance spray to the motors while personnel are on the roof, if maintenance is scheduled.