I have an arduino on a breadboard and having an issue with the voltage on the digital pin 13 outputing an low voltage when connect to a volt regulator. Why is this happening? because when the breadboard is connected to an Arduino UNO power that is connected to the same power supply it works perfectly fine. See images and descriptions below. Thank you for the help.
Notes: Power wires are connected at the bottom of the breadboard
Arduino on breadboard
9v - 300mA Power
L7805CV 5voltage regulator
Set to output LIGHT ON on digital pin 13
The voltage on the rails when breadboard is connected to power is 5 volts
The voltage on digital pin 13 when connected to power is 0.370 volts (why?)
The voltage on the rails when connected to arduino power is 5 volts
The voltage on digital pin 13 when connected to arduino power is 4.74 volts
Why is the voltage on digital pin 13 not the same when connected to an Arduino Uno Power to an Power supply using a voltage regulator?