I'm new in the Arduino world. I have these two power supplies, but I don't know if I can use them. The first one has a 500mA and 9V d.c. power output. The second one has a 300mA and also 9V d.c power output. Both of them are unregulated. The volt output of both of them was 17V when I measured them, but the are unregulated. The arduino that I am using is a Arduino Uno Rev 3.