Large Diameter 264 mm.
Small Diameter 244 mm.
Depth 24 mm.
Distance of deepest point from bottom edge along large axis 130 mm.
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The Focal Length is 139.56 mm.
This offset reflector is a section of a full parabola with a diameter of 484.39 mm whose vertex is at the bottom edge of the offset reflector. The full parabola has an f/D = 0.29, which determines criticality of focal length.
The focal point of the dish is 139.56 mm from the bottom edge of the reflector and 244.63 mm from the top edge of the reflector.
For operation with the main beam on the horizon with the feed at the bottom, the dish must be tilted forward so that the large axis is 66.55 degrees above horizontal.
Illumination angle for feed = 81.90 degrees on the large axis and 84.20 degrees on the small axis. A feedhorn with a 3 dB beamwidth of 49.16 degrees is needed, equivalent to the feed for a conventional dish with f/D = 0.65.
Gain at 50% efficiency = 26.73 dBi.If you do really well, you might get 60% efficiency for a gain = 27.52 dBi.
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