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<blockquote data-quote="futumsch" data-source="post: 722289" data-attributes="member: 321089">Hi Vipersan, I'm going to go a bit hypothetical now and contradict myself. I've had my head in JD Kraus 'Antennas' which reminded me of my good ole days of a ground station calibration engineer spending many cold days up on a hillside with a linear dish pointed at a transmitting circular dish to measure 'axial ratio'. What it boils down to, is that you might have a perfect parabolic dish, but a cross polarised signal (the opposite pol to the one you want) can interfere with the co-polarised signal (the one you want) and the polarisation appears elliptical. (and lot of mathematics with squiggly lines in that would take me a month to understand).I was calibrating 8-10 m dishes but the principle is the same, so I wouldn't discount tweaking your circular LNB for max signal. Its probably might make a gnats chuff of difference but squeezing every last ounce of signal at the LNB is going to mean better C/No through the rest of your system.Do I make sense? Its late.. I'll get me coat.</blockquote>

[QUOTE="futumsch, post: 722289, member: 321089"] Hi Vipersan, I'm going to go a bit hypothetical now and contradict myself. I've had my head in JD Kraus 'Antennas' which reminded me of my good ole days of a ground station calibration engineer spending many cold days up on a hillside with a linear dish pointed at a transmitting circular dish to measure 'axial ratio'. What it boils down to, is that you might have a perfect parabolic dish, but a cross polarised signal (the opposite pol to the one you want) can interfere with the co-polarised signal (the one you want) and the polarisation appears elliptical. (and lot of mathematics with squiggly lines in that would take me a month to understand). I was calibrating 8-10 m dishes but the principle is the same, so I wouldn't discount tweaking your circular LNB for max signal. Its probably might make a gnats chuff of difference but squeezing every last ounce of signal at the LNB is going to mean better C/No through the rest of your system. Do I make sense? Its late.. I'll get me coat. [/QUOTE]

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