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Old 09-12-2010, 10:28 AM
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telemarker (Keith)
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telemarker is offline
 
Join Date: Mar 2008
Location: Canberra, Australia
Posts: 601
Quote:
Originally Posted by scopemankit View Post
Try and move your counterbalance to ensure slight bias in the opposite direction, so the motor is always pulling against a load.
Thanks for the reply chris. I'm afraid its not a simple balance problem as the motor is actually driving the movement faster than the sidereal rate until it decides it has moved its sufficiently, then it starts sidereal tracking. By this time its way off target.

Quote:
Originally Posted by AndrewJ View Post
This is normally due to bad drive training results.
Ie when you finish a slew, and the scope needs to reverse direction, the scope slews at approx 2x sidereal to account for the "theoretical" backlash before reverting to normal tracking.
If you are overtrained, it will effectively slew too far whilst applying the expected lash, vs the real lash.
What are your current drive train/backlash numbers?
( not percentages, but drive train values )

Andrew
Thanks Andrew, I wasn't able to fire it up last night due to atrocious weather and the amount of water inside my shed but this sounds like a likely suspect. I had only recently replaced the handset, stripped/regreased the mount and done a warpsdrive upgrade but hadn't retrained the drives. This is now on the to do list once the weather clears and I dry my shed (I keep every thing off the floor luckily).

Thanks for the responses guys.
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