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Re: 23/13cm dual helix feeds - response



>From: "Gunther Meisse" <gjmouse@neo.rr.com>

>Rafal,
>I have just completed building a dual 23/13cm Helix feed for a 60cm >dish. 
>I will use same as a portable rig. So far I have tested the >13cm downlink 
>portion with very good results. I am comparing it with >my 1.2m dish. As 
>expected I see about 3db drop in levels.

This is rather amazing in and of itself, because gain in a dish antenna is a 
function of area and not diameter...

This means going from a 120cm dish to a 60cm dish you should have seen 
levels go down 6 dB.  It's true, I'm not making this stuff up...

3 dB would be more like going from a 4 footer (120cm) to a 3 footer 
(90cm)...

Fred W0FMS




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