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19 Sep
2008
19 Sep
'08
4:49 p.m.
A digital encoder would be the most accurate. USdigital http://www.usdigital.com/support/glossary#glossary_opticalencoder manufactures inexpensive encoders. With these and a step servo drive in example a Gecko drive http://www.geckodrive.com/product.aspx?c=2&i=14456 one could build a rotor that would be accurate to a thousand of a degree.
Fred KF0AK