Re: Identifying Peaks in the PECPrep Periodicity Plot In the PHD2 Guide Log - Somewhat #ExploreScientific #iEXOS-100 #EXOS2 #TECHNICAL

Jerry Hubbell - Explore Scientific VP Engineering

On Tue, Oct 1, 2019 at 12:10 PM, Robert Hoskin wrote:
Can you quantify what you're seeing as too tight/too loose?
Hi Bob, 

The only advice I can give as to how to maybe quantify the adjustment is to work the problem backwards as you have to see a marked reduction in the PE at 13.33 seconds and at that point, you will know that the belt tension is good. Then you may be able to quantify the amount of "give" or tension on the belt.  It's all relative though, if your peak at 13.33 seconds is half the size as it is at 133.3 seconds, then that is probably good enough, and if you can get your 133.3 second period well below your 600 second period, then you are doing great.

I think the main goal is to minimize the PE of the belt drive system and have only the 600 second period as the most significant PE. You would then be left with adjusting your worm somehow to minimize the PE, but that is a different problem where you are dealing with the runout on your worm and the differential meshing of the main gear.
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at
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