I have constructed a series circuit to power the arduino uno from a 12v to 14v battery. The battery fluctuates do to solar panel. The circuit continuously supplies 8.5 to 9.2v. The supply is plugged into the barrel jack. The 5v output pin is only giving me 3.3v. When using usb from computer to usb on arduino I get 5v and also get 5v when using ac adapter to arduino barrel jack. Any help is appreciated.