Running stepper motors with driver signals and interfacing with transistors

hello,

i have 28byj-48 stepper motor , driver cool, learned have send sequence signals rotate it.

at work gave me split air conditioner stepper motors run @ 12v. went home , started think how dive them.

i thought 1 of popular driving ckts saw on google images transistor ckts.

so have s9018 ok application.

so connected them , started face problems connection.

i leaned 1 of problems grounding of ckt.

here's draw of stepper motor:



here's ckt:



regards,

i suspect after 53 posts should know post relevant details of want useful advice. also, what's purpose of 75% of post being white-space?

post link datasheet new stepper motor, or @ least post clear photo of it.
measure coil resistances , post details

the 28byj unipolar motor. if new motor bipolar need different type of driver - maybe pololu drv8825. important know how current motor can take before choosing driver.

have read through stepper motor basics

...r

Arduino Forum > Using Arduino > Motors, Mechanics, and Power (Moderator: fabioc84) > Running stepper motors with driver signals and interfacing with transistors

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