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<blockquote data-quote="wium" data-source="post: 655412" data-attributes="member: 202123">I quote an email received from Eric Johnston of Satsig.net for its interest value.The set up angles for a polar mount are a compromise approximation.Therte is no perfect formula that give the correct angles.The satellites are in a circle above the equator.The polar mount makes the beam point around a cone.The apex of the cone points in some direction(polar motor axis main angle) and the spread of the cone is related to the other angle.If the dish were far above the north pole the beam would make perfect pointing all round.On the equator the polar mount is simply up from east via above the west.Only on the equator,or far above the north pole,is a polar mount mathematically perfecttly correct for all satellites.ELSEWHERE THE CONE CAN NEVER MATCH INTO THE CIRCLE EXACTLY.Errors of about .1 deg are typical.For a particular site you can set the main angle to the latitude and it works reasonably well.You&nbsp; might get better results with my angles which are slightly different.Note that a polar mount wont work with a very big dish or high frequencies as the errors are more than the antenna beamwith. (end of quote)I have avoided the declination dish setting due to the bad scale markings and using the elavation angle of the apex sat(at true north/south,imaginary or not) measured from the top of the lnbf to the bottom lip of the satellite dish coupled with site elevation angle from the Satsig web site (slightly higher than ones official latitude) with much success.Of course final fine tuning is still necessary.</blockquote>

[QUOTE="wium, post: 655412, member: 202123"] I quote an email received from Eric Johnston of Satsig.net for its interest value. The set up angles for a polar mount are a compromise approximation.Therte is no perfect formula that give the correct angles. The satellites are in a circle above the equator.The polar mount makes the beam point around a cone.The apex of the cone points in some direction(polar motor axis main angle) and the spread of the cone is related to the other angle.If the dish were far above the north pole the beam would make perfect pointing all round.On the equator the polar mount is simply up from east via above the west.Only on the equator,or far above the north pole,is a polar mount mathematically perfecttly correct for all satellites.ELSEWHERE THE CONE CAN NEVER MATCH INTO THE CIRCLE EXACTLY.Errors of about .1 deg are typical. For a particular site you can set the main angle to the latitude and it works reasonably well.You might get better results with my angles which are slightly different.Note that a polar mount wont work with a very big dish or high frequencies as the errors are more than the antenna beamwith. (end of quote) I have avoided the declination dish setting due to the bad scale markings and using the elavation angle of the apex sat(at true north/south,imaginary or not) measured from the top of the lnbf to the bottom lip of the satellite dish coupled with site elevation angle from the Satsig web site (slightly higher than ones official latitude) with much success.Of course final fine tuning is still necessary. [/QUOTE]

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