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From: mfogarty@netcom.com (Michael Fogarty)
Subject: Re: Source for 8-bit optical binary rot. encoder?
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Date: Sat, 25 Feb 1995 20:02:51 GMT
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Results of my week-long search for an eight bit, optical, absolute,
binary or graycode rotary encoder:

1.  Hewlett Packard doesn't make absolute encoders
2.  Oak Grigsby makes a four bit binary or gray code that sells
   for about $50 in the Newark catalog.
3.  Oak Grigsby also makes a five bit version.  I don't know the
   price.  Five bits is as high as they go.
4.  Penny&Giles make some nice panel mount items, but I couldn't
   get anyone in their Santa Monica or Mass. offices to admit that
   they make absolute encoders.
5.  Gurley Precision Instruments makes 16 or 17 bit rotary, binary,
   optical encoders.  I figured, "Great, I'll just get one of those
   and throw out the bottom 8 or 9 bits!"  Then I learned that they
   cost in the range of $1300.00 each.  We could make one for much
   less than that.

In the end, it looks like we're going to go with some kind of
incremental encoder.  Apparently there is a part out there (lm628, or 629)
that will handle eight-bit counting and an index pulse.  It's not
ideal on an SRL machine, but oh well...

Thanks to the many who mailed or posted.

mfogarty
software engr.
Survival Research Labs 
-- 
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	  "I mistrust all systematizers and I avoid them.  The will
	to a system is a lack of integrity." - Friedrich Nietzsche,
					       _Twilight of the Idols_,
					       Maxims and Arrows No. 34.
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