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Old 02-02-2015, 10:24 PM
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wasyoungonce (Brendan)
Certified Village Idiot

wasyoungonce is offline
 
Join Date: Jul 2006
Location: Mexico city (Melb), Australia
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Quote:
Originally Posted by John K View Post
...
This is an image of my scope, and the drive is made my Losmandy.JohnK.
John can you identify the drive...is it a Losmandy Digital drive system or Gemini.

I cannot tell from the pic. I didn't know JMI were using Losmandy drive systems?

Brendan

edit:
After a little search I found JMI has a unit fitted that looks like the Losmandy Digital Drive stepper system. Different front cover though.

So if it is running fast in RA then lowering the voltage in will not slow it at all. The system uses a crystal oscillator and microcontroller to determine the RA rate. A 9 metre FL is very unforgiving it's possible the scope is biased too heavy to one side perhaps. The other thing possible is that the drive system is fast in RA, the probable cause would likely be the crystal or the RA stepper motor. These can "cog" and fail to step (depending upon type of stepper motor used).

Maybe swap RA & DEC motors to see how this goes as first step.

Last edited by wasyoungonce; 02-02-2015 at 10:40 PM.
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