Caveat Lector wrote:
Ok I screwed up by referring to the Sommer antenna site for Capture Area

But I was taught that antenna gain is a function of Aperture - part of the
classic radar range equation
https://ewhdbks.mugu.navy.mil/2waymon.htm

For Aperture discussion see URL:
https://ewhdbks.mugu.navy.mil/ANTENNAS.HTM

So would be interested in your comments on Antenna aperture and antenna gain
and capture area


If you have an antenna of a known type that happens to be
area-dependent on gain, you could tie gain to physical size (physical
aperture) through a formula.


That isn't to say the relationship holds in anything other than a
specific case. For example if the dish is not formed correctly gain
with drop, despite the dish being a size that would otherwise have
higher gain. This means the capture area would be smaller than you
calculated for a "good dish".

Same for feed system. If the illumination system blocks the area of the
dish or has design flaws, and if gan drops, the effective aperture
would be less for the same size antenna.

Does this make sense to you?

73 Tom