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Re: 2.4GHz S band helix feeds, et al.



Ed, Bob,
 
Thanks for your comments.  The WiMo helix doesn't look very long, in comparison to some hb helices I've seen in various references, and not nearly as long as a regular helix antenna for MMDS or similar appl on S band.  With radome and all, it's only about 6" in length from the rear bulkhead to the forward end of the radome and about 3" in diameter.  Would it be worth the effort to hb a reflector and just attach it to the rear bulkhead, or must it have that 1/4" wide shim on the first 1/4 turn of the first winding about which I've read?
 
In a roundabout way I guess I'm asking you two, and other bb readers as well, if I've wasted about $100 on a helix feed I can't use.
 
Why would a helix feed like the one I have be on the market without a reflector?  Are there applications for one where the user wouldn't be too concerned with background pickup?  If I am almost exclusively interested in receive capability on mode S, the reflector is aimed at an upward elevation and the feed is pointed at the reflector to capture maximum signal so that nothing is aimed at the ground, do I need to be worried about the reflector?
 
Lastly, if the feed I have is no good and cannot be successfully integrated with a PrimeStar dish as Bob suggests, does anyone offer for sale a helix or patch feed for mode S that can be used with the AIDC 3731 and a parabolic in the 60cm dia x 25cm depth area?  That's the approximate size of the large BBQ dishes I have on hand and was going to enclose with screen if I couldn't make the DirecTV dish work.  I haven't a lot of time to experiment, nor funds to spend on a bunch of test gear, so I'd really prefer something that works COTS.  It's not that the physics of this is totally beyond me, just that my resources to play on the radio are limited and my threshold for frustration is low.  What is it about spouses?  They think you can accomplish your radio goals in 15min a day!
 
73, Ray KA8SYX
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