Technical information

OM56_Rev G Page 12 of 28
2.2 General Subreflector Alignment Guidelines
The primary goal of Subreflector alignment is for the Subreflector to be properly centered and for the height to
be adjusted to the correct focal length for the antenna.
Keep the following guidelines in mind during Subreflector alignment:
 A tape measure is generally used in order to center the Subreflector
 Measure from a repeatable location, running the tape measure from the 4 locations where the strut ends
meet the main reflector to the inside edge of the Subreflector
 For centering measurements, a zero delta between all is ideal
 Focal length is measured from the antenna vertex to the edge of the Subreflector at the three Adjustment
Rod locations on the Subreflector
 Target focal length distance is determined by antenna type
 Normally, the process of centering the Subreflector then the Subreflector height is repeated until both
centering and height are “nuts on” precise