archive: SETI Formula to calculate a dish's focal point

SETI Formula to calculate a dish's focal point

Ray Shank ( res@mail.org )
Sun, 20 Sep 1998 17:06:51 -0500

Okay, Brainiacs.

I was given a formula to calculate the focal point of a dish of unknown
properties. I was wondering if it was ok to use or if there was something
else I should consider. Here it is:

Diameter squared divided by 16 times Depth. (Dia * Dia) / (16 * Depth)

Is the focal point where I put the opening of the feed horn, or the
position of the dipole within? I'm using the SETI feed w/scalar.

Ray Shank - res@mail.org
Argus Observatory EM26eh
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