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ChrisV
24-05-2017, 09:21 AM
Guiding on my CGEM has been okay but I've noticed there's a reasonably large (1.5-2" peak-to-peak) periodic cycle on the RA axis that PHD2 guiding will not get rid of.

So I did PEC training on the hand controller with PHD2 to applying the error corrections. The first time all went okay but I bumped the mount while I still had PHD2 running (stupid).

The next time I tried PEC training the mount started making this weird clattering noise. It wouldn't stop. Turned off the mount, redid the star align, started PEC training again and got the same clattering noise.

What's going on ?
Attached are the PHD2 calibration and a guiding log from my mount prior to PEC training if that's any help.

Lognic04
24-05-2017, 10:24 AM
Could it be backlash? (as in the gears touching, i have heard this noise before)

LewisM
24-05-2017, 03:16 PM
Gears touching is binding. Backlash is the opposite - it's the gap between the gear teeth such that when the load is removed or reversed, there is a pause in movement in the time it takes to reengage the gears.

ChrisV
24-05-2017, 07:20 PM
The noise is exactly the same as this I found on youtube.
https://www.youtube.com/watch?v=fsOZ6_icymY