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Old April 28th 05, 12:11 AM
Richard Fry
 
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From: "Richard Harrison"
Richard Fry posted a beautiful picture of a Harris / Gates test facility
in which an antenna tower is rotated and tilted up to 90-degrees, I
suppose. Nice way to get the antenna pattern. Hope Harris had a
government contract number to charge that job to.

________________

Azimuth patterns were taken by spinning the antenna+tower around a
horizontal axis centered above the two trestle supports you see in the
scanned photo. The AUT is positioned broadside to the source antenna.

Elevation patterns were taken by spinning the whole assembly in the
horizontal plane, on the horizontal centerline of the antenna+tower
assembly. The trestles sit on a huge wooden beam which itself is supported
by, and centered on a motor-driven turntable -- making that possible.

So both sets of patterns can be taken without needing to put the
antenna+tower in the vertical plane (no tilting to 90 degrees is necessary).

However we had several other positioners for vertical antennas to use when
the measurement of elevation patterns was not required.

Yes, this customer had deep pockets, but was not a government agency. Just
a major broadcast group.

RF