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<blockquote data-quote="a33" data-source="post: 1089856" data-attributes="member: 332642">So, I've done some further analysis.The drawing of Harm Lok suggests 270 degree rotation; that would be more than a polar mount is capable of, I think. 180 degrees would be a (non-reachable) absolute maximum.In his equation, he has the 0 degrees at the bottom. So the movement would be from -90 to +90 degrees.I looked up my old notes, from October 2018. Found and derived my equation again.Other than Harm Lok, I use the range from 0 to 180 degrees.And of course, I added the B-BB in the equation.I got rid of the sin² and cos² in the equation, leaving just one cosine.(Originally I did this, using the cosine rule on triangles. But I could also derive the Harm Lok approach to eliminate the cos² and sin².)This has the advantage, that the vice-versa calculation (from actuator length to USALS angle) is also not difficult.&nbsp; <img src="https://www.satellites.co.uk/styles/default/xenforo/smilies/smile.png"&nbsp; class="smilie" loading="lazy" alt=":)" title="Smile&nbsp; &nbsp; :)" data-shortname=":)" />The equation allows eastside or westside actuator mounting, both giving the correct actuator lengths.Here the equation, and a (draft) document with relevant info.[ATTACH=full]130876[/ATTACH]Greetz,A33Edited: corrected a typo in the formulae.And I haven't checked yet, if the ZeroAngle equation is east/west-proof for actuator side. That'll have to be done later.</blockquote>

[QUOTE="a33, post: 1089856, member: 332642"] So, I've done some further analysis. The drawing of Harm Lok suggests 270 degree rotation; that would be more than a polar mount is capable of, I think. 180 degrees would be a (non-reachable) absolute maximum. In his equation, he has the 0 degrees at the bottom. So the movement would be from -90 to +90 degrees. I looked up my old notes, from October 2018. Found and derived my equation again. Other than Harm Lok, I use the range from 0 to 180 degrees. And of course, I added the B-BB in the equation. I got rid of the sin² and cos² in the equation, leaving just one cosine. (Originally I did this, using the cosine rule on triangles. But I could also derive the Harm Lok approach to eliminate the cos² and sin².) This has the advantage, that the vice-versa calculation (from actuator length to USALS angle) is also not difficult. :) The equation allows eastside or westside actuator mounting, both giving the correct actuator lengths. Here the equation, and a (draft) document with relevant info. [ATTACH type="full" alt="A33 Satellite Dish Actuator Length Equation for a certain USALS angle.png"]130876[/ATTACH] Greetz, A33 [I]Edited: corrected a typo in the formulae. And I haven't checked yet, if the ZeroAngle equation is east/west-proof for actuator side. That'll have to be done later.[/I] [/QUOTE]

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