Bob Perhaps my helix feeds would be applicable. Usually designed for off center dishes. With fewer turns you would have a wider pattern. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMESE%3AI... 73 Bob W7LRD Seattle -------------- Original message -------------- From: "Robert Bruninga" bruninga@usna.edu
How does one build a feed to properly illuminate a pizza
slice-shaped
reflector? Or is this a matter of 1/4 of a 10' dish being
still so
over-kill that you only use the fat end, and under-illuminate
that?
Well, presumably one will be using this on S-Band either for 802.11 or other 2400 MHz purpose so one has to build his own feed anyway. Probably a dipole over a splashplate. That is typically a good feed for a typical .4 F/D dish? If that is so, then when it is used to illuminate just 1/4th of the dish area, then there is spillover and a few dB are lost. Maybe a good feed for the 1/4 quadrant dish might be a dipole over a splashplate with a director?
Someone who is good on feeds might suggest the right answer here... But in any case, one is not trying to illuminate the tastey end tip of the pizza slice, but generally the center of the crusty end...
De WB4APR, Bob
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