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<blockquote data-quote="franksanderdo" data-source="post: 749795" data-attributes="member: 357262">Hi JanHSubreflectors on in offset Multifeed are not that much another issue, but thos are very hard to kalkulate (at least for me ;-) )As I said it is a bit tricky to modify a prime focus dish for holding the LNB. I was lucky with my 1.4m as there was the structure of the disk and the mount helping a lot. I only needed some hose clamps to get the LNB fixed. Not nice, but working :-DHi fta-eliteThe calculation for the sub reflector is very similar to the main reflector.The definition of focus length is again the distance to the lnb. The diameter and the depth I have seen some where can be calculated for optimum gain. I figured it more like:Diameter as small as possible (used the feed horn diameter) depth was then calculated out of focus and diameter.I only tried the cassegrain configuration, but I believe if you reflector follows the same shape on both sides (mine did not, it was flat on the back side) you easily can try both.See you aroundFrank</blockquote>

[QUOTE="franksanderdo, post: 749795, member: 357262"] Hi JanH Subreflectors on in offset Multifeed are not that much another issue, but thos are very hard to kalkulate (at least for me ;-) ) As I said it is a bit tricky to modify a prime focus dish for holding the LNB. I was lucky with my 1.4m as there was the structure of the disk and the mount helping a lot. I only needed some hose clamps to get the LNB fixed. Not nice, but working :-D Hi fta-elite The calculation for the sub reflector is very similar to the main reflector. The definition of focus length is again the distance to the lnb. The diameter and the depth I have seen some where can be calculated for optimum gain. I figured it more like: Diameter as small as possible (used the feed horn diameter) depth was then calculated out of focus and diameter. I only tried the cassegrain configuration, but I believe if you reflector follows the same shape on both sides (mine did not, it was flat on the back side) you easily can try both. See you around Frank [/QUOTE]

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