Jim Lux wrote in
:

Owen Duffy wrote:
....
In high performance systems, I perceive a preference to not use G/T
as a metric for receive system performance.

This is hams, the preferences of which you speak? In the rest of the
microwave station world, I think G/T is a popular "one metric for
all", at least for things pointed at the sky.

Yes Jim, an omission on my part... hams tend not to use G/T... but yes,
the rest of the world recognises the value of G/T as a single metric,
especially for space comms.

I suppose one complication of G/T for EME is that the noise varies with
moon position and local elevation... but one thinks that a range of G/T
figures could be expressed to characterise a station's capability.

G/T for a Sun transit at high elevation would be a most useful metric for
assessing a station against state of the art.

Owen