UA performs an Extended UV scan in 0.5nm increments and stores the data to a UVJJJYY.nnn file. This is a ‘timed’ routine in that it starts on the next half hour after the command is given. On execution of the command, the prism is rotated to the UV dome, FW#2 is moved to the 1 position, FW#1 is moved to the 3 position, the iris is opened, and the tracker is pointed at the sun.