Hello everyone, I introduce myself are Ezio and I write from Italy.
Sorry for my english, but I’m forced to get help from google… 
For almost three years 
struggling with the construction of an equatorial mount of a telescope.
I have to control the two axes with two stepper controlled with Arduino Mega. The choice is moving towards the following engines (in descending order of torque):
Sanyo Denki 103H7123-0440 (2A 1,6ohm 0,83Nm)
Sanyo Denki 103-770-1640 (1,41A 2,6ohm 0,62Nm)
Sanyo Denki 103H-6704-0440 (2A 1,7ohm 0,52Nm)
As I thought about the Pololu driver DRV8825 pololu.com/catalog/product/2132. I like this because I have the opportunity to work with voltages (I thought 36V) and thus have more torque at higher speeds, and also will benefit me in the microstep 1/32.
I’m a little rusty in electronics (many years have passed from the school studies) for which to avoid buying wrong, I ask you some advice. In particular I’m not sure if the driver Pololu may be fine for engines that I have listed above.
Soon the mechanical part is almost finished, so I’ll be more sure of the actual pair that I’ll need. In the unfortunate event that I were to use a more powerful engine, such as the SECM8 (2.8 A 1.2 ohm 1.12 Nm), which driver works in microstep would you recommend?
Thank you all,
Ezio
