??????????? - axes balanced (done with worm removed during replacement)

??????????? - recently cleaned and re-greased whole mount (SuperLube)

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Data acquisition:

??????????? - ST80 guide scope (WO fixed mounting rings on a Losmandy dovetail) piggybacked on a C8

??????????? - ASI 120mm?

??????????? - PHD2 latest dev

??????????? - acquiring at meridian on equator for ~ 8 minutes

??????????? - polar alignment <1'

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Things I've tested so far and ruled out:

??????????? - correct RA divisor (sidereal)

??????????? - swapping cables

??????????? - dew controller off

??????????? - east bias (wouldn't expect this to do anything for a drift)

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Probably the most interesting observation is that when I acquire with the scope on the east side, the mount appears to track fast (star drifts east in PHD), but when I flip to the scope being on the west side of the mount, the RA drift in PHD is in the opposite direction. ?So is this clutch slippage, flexure, balance? ?I could test the clutches slipping I suppose by "tracking" a fixed object in the day and looking for any drift. ?Other things I could think of to test are swapping motors, worm mesh (but this shouldn't matter here), but would like to hear your thoughts before moving on.

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Thanks,

Keith

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