[amsat-bb] L/S helix feed

[Joe Leikhim]

Bob; I don't think the larger reflector will hurt S-band feed although the larger reflector will create some additional blind spot for the dish. This may not be a problem depending on the gain required. Could you share pictures or drawings of the concentric feed? I am very interested in all options for multiband dish feeds.

Message: 3
Date: Mon, 23 Oct 2006 23:46:52 +0000
From: w7lrd at comcast.net
Subject: [amsat-bb]  L/S helix feed
To: amsat-bb at amsat.org
Message-ID:
	<102320062346.26698.453D546C00022FD80000684A22058861720B9D04C999 at comcast.net>
	
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Hello
Questions on my current L/S helix feed.
I am building a dual L/S concentric helix feed for a 48x54 inch primestar dish.  The reflector is cut for  L band does that cause a problem with S band?  Where can I find a good design for a notch filter for S band to reduce desense?  Where does the focal point want to be on the helicies?  Or is it pretty forgiving.  Any other information is appreciated.
73 Bob W7LRD
Seattle

-- 
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

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