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[Jagho]

Hi All,
I'd like to use AstroEQ for Gemini G-40/G-42 mount. G-42 manual says, that you can "use any other controller that can drive bipolar stepper motors with at least 1A/phase". AstroEQ (DRV8825) can drive this steppers easily, I think. G-4x is Direct Drive System (main gear 432). My question is. What are the proper settings of AstroEQ for this mount ?
There are settings for other controllers:
http://www.jgao.pl/pliki/setupg40.pdf
There are other controllers for Gemini G-4x/5x (e.g Pulsar) but there are much more expensive and not better then AstroEQ.

[TCWORLD]

Hi,

Sounds like the motors will work fine with AstroEQ. The gear ratio also appears to be high enough - you get a resolution of 0.47 arcseconds/microstep.

I've attached a .conf file for the configuration utility for your mount.

I'm not sure what the top speed will be, but it looks like it should perform well. I've put ~400x as the goto speed in the config file, but you can increase or decrease this depending on whether the motors can't go that fast or can go faster. As the drive voltage is only 12V, this may limit the performance slightly but hopefully not too much.

Regards.
Tom.

[Jagho]

Thank you very much, Tom,
and as to setting current limit, I should use the method described in FAQs ?
or there is a better way ? I have some tools, oscilloscopes, multimeters etc.

Best regards
Jarek

[TCWORLD]

Hi Jarek,

Finally gotten around to updating the current limit page to include the better method of using a multimeter to accurately set the current limit.

Regards,
Tom.