I am using the program and schematic that came with the starter kit for the motorized pinwheel project. However, instead of 9v batter I am using a 8v battery cell from the airsoft gun. I did everything right, but i believe the problem is in the transistor. Any suggestions?
**The motor clicks when i press down the button, but does not fully rotate. However, when i simply connect the motor to the power source it fires rapidly.
Please post the schematic or a link to the schematic, it's virtually impossible to know what you have built with the amount of information you poster.
Having said that... Running devices on voltages below their normal voltage is likely to cause problems.
If you are using a transistor to switch things on and off there will be an additional voltage loss in the transistor of at least 0.5V,
Do this help?
This image is in this tutorial.
but i believe the problem is in the transistor. Any suggestions?
You probably need a logic level MOSFET like below.
Just to add a little more info to this thread, an "8v airsoft battery" is actually an 8.4v NiMH or NiCD battery pack, typically no less than 700mAh, usually 1500mAhr or more.
If the transistor requires 12v, a 9v battery may have been able to work, but a 8.4v battery may not.
Hi, what is the part number on your "transistor"?
Tom................ 
Came with the arduino starter kit "IRF 520"