3-dB down each way. For satellite reception this is not too bad. However, some satellite's circular pol (CP) signals are elliptical (have some linear component) if they have a squint angle with the ground station. Thus the use of the linear-pol Arrow and the "Arrow Wave" works quite well.
In the past being able to switch sense in CP helps because satellite squint can result in a reverse of polarity sense. Then you have AO-51 that utilizes opposite sense CP on different frequencies to improve isolation in the onboard receivers.
HNY & 73, Ed - KL7UW
At 06:54 AM 1/1/2008, Andrew Rich wrote:
If I have this correct.
- LHCP recieved on a RHCP can knock your signal down by some 20dB
- LHCP matched with LHCP will result in a good signal.
So how does a linear antenna equate when receiving a circular signal ?
And the other way around, a circular receiving a linear signal ?
Andrew Rich VK4TEC
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73, Ed - KL7UW ====================================== BP40IQ 50-MHz - 10-GHz www.kl7uw.com 144-EME: FT-847, mgf-1801, 4x-xpol-20, 185w DUBUS Magazine USA Rep dubususa@hotmail.com ======================================