[amsat-bb] Circular polarisation question

Phil phillor at telstra.com
Thu Apr 15 04:19:06 PDT 2010

Thank you for reading this.

Ten years ago I built a pair of circular polarised aerials primarily for 
satellite use. The UHF aerial has 12 elements in each plane while the VHF 
aerial has 6 elements in each plane. My UHF received signal strength often 
seems to be below that of other stations and so I'm rethinking how I have 
set up these aerials. The received signal strength via VO-52 is S7 at the 
best, without a pre-amplifier, and so I'm happy with that. The UHF aerial is 
where the problem is even thought they are set up in the same way.

Both aerials are mounted in an X orientation. One set of elements is a 
quarter wave ahead of the other set. Because of the X mounting I cannot 
tell if the vertical set is ahead of the horizontal set or not. Each aerial is 
fed via a power splitter via equal length cables.

My question is; does this sound like a correctly set up right hand polarised 
aerial? Originally I thought it was now I'm not sure.


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