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Re: IC-910 / 3731

On Thursday 13 November 2003 16:19, Anthony Monteiro wrote:
> Hi Drew,
> Nice to hear from you (enjoyed the symposium!)
> I don't see how a center fed 60cm dish could work very
> well since the feed blockage is so severe at 2.4 GHz
> whereas a 60cm offset-fed would seem passable if
> fed correctly. Don't you think?
> I think most of the problems with offset fed dishes
> is that people try to feed them with a helix which
> picks up too much ground noise.
> Any comments?
> Tony AA2TX

Hi Tony et all,
   a center fed 60cm dish would see about a .9dbic blockage with a 5" feed,
using one of Roberts patches you would have a blockage of 3.5" (about)
for a loss of only .2 dbic, the dish overall would have about a 19 to 20dbic 
gain,  true that people tend to over illuminate with helixes, but adding more 
turns should help that...


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