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Pazuzu Pazuzu is online now
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Join Date: Apr 2008
Location: Houston TX
Posts: 8,745
Quote:
Originally Posted by Eric Hahl View Post
The included (as measured) periodic error graph for the GEM 45 shows less than 5 arc seconds and about 6.2 peak to peak...impressive.
Test that, all of the iOptron PE graphs I've seen end up being WAY optimistic compared to the actual usage. I believe that they even state in very tiny letters that they measure the worm/spur gear alone, in a lab condition. Once you install them on shafts, and add motor drives and timing belts, bearing sag, mount sag, etc they show much worse. A smooth PE that is +/- 50 arcseconds is better than a choppy one that is +/- 10 arcseconds.
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Mike Bradshaw

1980 911SC sunroof coupe, silver/black
Putting the sick back into sycophant!
Old 12-22-2021, 03:52 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #698 (permalink)