mvp, I believe I saw you discussing a source for the McClellan Data with someone else a while back, he asked about the formula and so on. Here, FYI: <A HREF="http://www.mcoscillator.com/Data.html" target="_blank">http://www.mcoscillator.com/Data.html</A> <A HREF="http://www.decisionpoint.com/Glossary/AboutMcOsi.html" target="_blank">http://www.decisionpoint.com/Glossary/AboutMcOsi.html</A> Not a long history, but here you can get the data with the formulas readily in Excel (its updated regularly and if you collect it long enough you'll get a history): <A HREF="http://www.mcoscillator.com/user/OSC-DATA.xls" target="_blank">http://www.mcoscillator.com/user/OSC-DATA.xls</A> Regards,