Plotting antenna pattern from Sun noise
 

Jim Lux wrote in
:

....
And, really, what precision do you need for pointing/plotting?

Presumably folks are looking at fairly wide beamwidths (so that the
sun size (1/2degree) is a small fraction of the beamwidth)
5 degrees?
1 degree?


Jim, I suggested in my article that the Sun technique was most suited for
beamwidths down to about 3 deg. As you have noted, there are a large
number of other factors that become relevant at small beamwidths, and the
most significant I think is the beamwidth correction factor to account
for the Sun's departure from being close to a point source, then as you
note the frequency dependent diameter of the radio Sun and the
distribution of the Sun's intensity.

So, down to 3 deg, the macros and formulae in my spreadsheet should be
more than adequate.

My thinking was that if you have a narrower antenna beamwidth, you
probably have sufficiently high G/T to use one of the radio stars which
will have much lower diameter.

Owen