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CGEM newbie question on slewing.

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#1 southbay


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Posted 28 September 2012 - 01:55 AM

I got CGEM DX a few weeks ago, and am trying to test run to see if the basic function works. I'm not trying to test the accuracy in pointing the stars or tracking yet, but just make sure slewing works as the first step.

When trying one star alignment, I selected the star and press the enter key. My understanding is that the mount is suppposed to slew to the target star. What I observe is DEC sometimes moves, but, at most of the time, it stays at the initial position that is set in a way DEC index marks align. It doesn't move in RA direction at all, however, I can see that the black ring between two RA index marks shown in the below pic rorates.

I'm not sure if I need to put a scope and counter weight to operate correctly. Currently, no scope or counter weights/shaft etc. are on the mount.

I'm a newbie and puzzled if this is an expected behavior while running one star alignment.
I'd appreciate for inptus from those who have experiences with CGEM/CGEM DX.

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#2 orion69


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Posted 28 September 2012 - 02:21 AM

Did you tighten RA and DEC locks?


#3 EFT


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Posted 28 September 2012 - 10:40 AM

First, you need to run the mount balanced, even if you don't have a scope on it. No counter wieght = no balance. Running the mount completely unbalanced (with the clutches engaged) is not good for it. You will probably need to load a scope on it since you cannot easily balance the mount with nothing on it.

Second, it sounds like you have the clutches released. When that is the case, the ring that you have shown in your picture will rotate while the RA head does not move.

Finally, make sure that you are using a sufficient power supply. I recommend a minimum of 2.5 amps for a wall supply and a good sturdy 12V for a battery supply.

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