Ok, so I am trying to create a transistor switching circuit so that when i put voltage on the base pin of a Bipolar junction transistor (NPN) it will turn on a motor current. After much frustration the circuit doesn't work. I have the motor wired from the emitter pin to the ground and +9 VDC on the collector. My microcontroller pulls the base pin to 5VDC. Should I use a opto isolator? Or should I rethink the transistor circuit? Thanks!-Waldo