elevation 	max. tracking
(deg.) 	("/sec.)
20 	126
25 	121
30 	115
35 	108
40 	100
45 	91
50 	81
55 	71
60 	60
65 	48
70 	36
75 	24
76 	21
77 	19
78 	16
79 	14
80 	11
81 	8
82 	6
83 	3
84 	1

Notes:

At the moment the maximum antenna velocity for tracking a source is 150"/sec. Below that value the tracking error is good, we could say that the error is below 1". At tracking velocities higher than 150"/sec. must be avoided because the antenna switch to another controller less precise (used for large displacements in the sky) and then there is a steady pointing error about 10".

The previous velocity 150"/sec. is in altazimuth coordinates. Just tracking a source at antenna low elevations implies antenna altazimuth velocities about 15"/sec. This altazimuth velocity increases at high elevations reaching values higher than 150"/sec. at higher antenna elevations than 83 deg.

If in addition to the own movement of the source in the sky the observer request a scanning velocity, then the maximum antenna elevation must be corrected to avoid exceeding the 150"/sec. The table above resumes how much should be the maximum scanning velocity requested by the observer depending on the antenna elevation.