> Or you measure also with accurate bench meter and put a calibration > factor in SW. Yeah. I think that comes under >> ... understanding their limitations. :-) > Then limitation original test gear, temperature and ageing drift. Largely yes. Still some second order effects from eg temperature drift but much less than the likely effect from initial component tolerance errors. Russell --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .