When I hooked up my stepper control box, I had lots of noise from the step & direction lines going to the motor leads, this made the motors do wierd stuff! One of the gurus on this site told me to use shielded cable for everything, and only ground one end of the shield! This has made everything run perfect, no hum, no lost steps, now radio voices from the motors! Yes, voices & music! I thought I was going bonkers!
Here is a greate site for getting multi conductor shielded cables!
http://www.action-electronics.com/cabl-prc.htm
Good luck, hope this helps!
Eric
http://kiersteadskis.com/cnc-router/cnc-router.htm
www.widgitmaster.com
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