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Effect of Wind

It is clear from Table 3 and the Fig 6 that the mechanical effect of wind on the antennas is not the dominant cause of pointing fluctuations. The night with the strongest wind (October 1 tex2html_wrap_inline1034 ) had actually one of the lowest r.m.s pointing fluctuations. On that night the elevation pointing of antennas 4 and 5 (and to some extent antenna 1) showed a drift by about 5'' in about half an hour while the wind increased from 6 to 8 m/s (fig. 5).

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Figure 6: Attempt to correlate observed pointing errors with wind velocity.