Jonathan Hancock wrote: > Hi all - just a quick update... > > I managed to get a square wave o/p from the original encoders using a > high-speed comparator as Jon suggested. It works ok but every now and > then stops working or seems very erratic. I know the original Pumas > 'folded up' on themselves occasionally due to encoder problems, so > maybe there are problems with mine. Bearing that in mind, I think it's > going to be safer to swap them out for modern ones. I've been looking > at the USDigital E5 > (see http://www.usdigital.com/products/encoders/incremental/rotary/kit/e5/ > ) which give A,B and Index square wave o/p's. Has anyone used these or > can you recommend another type please? The originals have 250 counts > so I'm guessing I should go for the same. The old, high-end encoders usually had 4 sensors, and obtained an analog differential signal from each optical track. This gave them an opportunity to eliminate fading of the light source or threshold shift in the sensors due to heat from the system. If these have light bulbs, you might just put in an infra-red LED. If they only have two sensors, then the old LED may have faded, but they can be hard to replace in some models. A new Renco ABZ encoder can be had for as little as $50 in a wide variety of styles and sizes. Hopefully, one of their standards will be a perfect fit.
Jon ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
