The Meade LX200 12-inch f/10 telescope at our observatory has been our main instrument since 2003. It has worked very well over the years, but there are a few minor items that can annoy me.
One of them involves slow motion in the Declination direction. If one moves the telescope one direction -- say, North -- and then makes another motion in the opposite direction -- South -- then there can be a slight delay. This sounds like backlash, but I think something other than gear mis-matches may be happening.
Take a look at the interior of the Dec drive. If one removes the plastic cover, one can see the innards:
Ignore the dead insect. It's not part of the problem.
Here's another view, showing the transfer gears more clearly.
The main symptom is: when I push the handpaddle's "move in Dec" button, if the motion is opposite to the previous slew, the motor shaft does not immediately start to turn; instead, there's a delay between "press the button" and "drive shaft turns". Moreover, this delay is longer for slow slew speeds. I made measurements earlier today:
slew speed delay between "button press" and "shaft turns" (sec)
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2 (4x) 35
3 (8x) 9
4 (16x) 4.7
5 (0.25 deg/sec) 1.4
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The handpaddle is an AutoStar II running software version 4.2g. I tried using the "Anti-Backlash" setting in the Dec/alt direction to fix this problem. However, the delays were the same within my measurement uncertainties for all the following Anti-Backlash settings:
001% (the default)
050%
150%
So, at this point, I'm stumped. I've posted a message to CloudyNights and hope that someone will give me ideas.