Gordon, Oct 5
The Gill windsonic at base was installed with no concern about its orientation.
Today Tom calibrated the data scope, then measured the sonic boom azimuth (with declination=0), getting the following readings:
38.2 |
37.5 |
37.1 |
36.6 |
35.1 |
35.8 |
36.4 |
35.4 |
mean=36.5 |
The magnetic declination here is 10.5 degrees. So the boom azimuth is 36.5 + 10.5 + 180 = 227.0 degrees wrt true north.
Then we removed the sonic and boom from the tower to figure out the orientation of the sonic relative to the boom.
By putting a ruler along the transducers and some advanced trig we estimated that the north arrow on the sonic is 2 degrees clockwise from the boom.
So N on the sonic is at 229 degrees true.
Entered this as the offset angle in $ISFF/projects/METCRAXII/ISFF/cal_files/noQC/dir_base_10m.dat.