From: "Tom Krajci" 
To: 
Reply-To: "Tom Krajci" 


From: "Larry Davis" 

>    Will a stepper motor make a reasonable clock drive for RA tracking?

I see no reason why not.  Others have done it.

>    So far everything I've found to opperate a stepper has been way
more
>complicated than necessary to preform this function, or so it seems....

Yes, Mel's system at:  http://www.bbastrodesigns.com/cot/cot.html is more
complex, but that's because it's meant to use one motor for both tracking,
and high speed slewing.  That means he's really extended the speed range
for a single motor.  I find that very handy.

>     2.   vary speed to match mechanical ratio of scope to sidereal
rate (
>I'm not sure how fine a speed control is available with stepper
controlers
>or how it is achieved )

Part of fine speed is achieved with the ratio of gear reduction that is
used.  Part of it is achieved with the use of microstepping.  Part of it is
done with software control of the micro stepping rate.

Are you sure you only want RA rate tracking with some slight adjustments
for guiding?  Would you also want high speed slewing capability as well?

Tom Krajci
Tashkent, Uzbekistan


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