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Help shopping list DIY motorized dob

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#1 astronutski


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Posted 19 July 2021 - 10:29 PM

Hey guys, I’m getting back into scopes after 10 years or so ‘slumber’ and am focused on motorizing my home brew 24” f/4 dob. I just get overwhelmed and my eyes gloss over when looking at websites trying to figure out where I’m at and what I need to acquire yet. Obviously money is not abundant.
I have sky commander xp4, two decent encoders (dk models offhand but I can check tomorrow, I do remtt E need they were bought from astrosystems and 8192 comes to mind). I have two Pittman gm9236c534-r2 5.9:1 servo motors. Dk if those have encoders or would the ones I’m using with sky commander work?
Besides all the retrofitting to the scope itself what else will I need? I imagine some gears a) for the servos, and b) for the alt/az axes.
I’d have to make a clutch because I hop all over the sky.

I suppose I’ll need an expensive controller. Eons ago I was absolutely sold on Mel’s bbastrodesigns setup, but fear and intimidation put that on hold. So here I am 10 years older and raring to dive into this as learning as I go and find out Mel’s no longer doing that system. Although it would be simpler to plop down a bunch on a complete package I don’t want to do that since I have (what I think are) a lot of the main components already.
Plus, in the years gone by those fantastic raspberry pis and arduino have sprung to life. (I have ample XP with rpis, but none with arduino).
Anyway, what’s left on the shopping list I’ll need to make this dream happen finally. I’m more interested in the tracking than the goto. Goto would be nice, but my main interest is the tracking. Not for photography and I don’t care at all about field rotation. This is a pure visual scope.
Any help greatly appreciated!!!

#2 cuzimthedad


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Posted 20 July 2021 - 11:05 AM

Moving to Reflectors

#3 Bill Jensen

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Posted 20 July 2021 - 11:54 AM

Welcome back to CN. You may want to check out Sitech's drives. 



Dan Gray's drives are pretty nice. I don't own one, but have seen quite a few scopes with those drives in action. 

#4 Tom Stock

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Posted 20 July 2021 - 10:19 PM

If you are mostly interested in tracking, how about a simple equatorial platform.


Push-to and an equatorial platform is such a nice combination and is far lighter, uses less batteries, and the scope still works fine with or without the platform.


Alignment is also much faster and you are free to just pan the sky without mashing buttons to do it.


You can build a platform yourself for about $100 at today's wood prices.

Edited by Tom Stock, 20 July 2021 - 10:21 PM.

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