My name is Dani and I started using Arduino some months ago.
Lastly I tried to build a line following and at the end it worked out. All the time i had been using the USB connection to power Arduino but i thought it would be better to use the power jack so the line follower could work without the pc. I used a 9v battery and i soldered the wires from the battery to the adaptor.
When the line follower is stopped a LED is on. It works perfectly with the USB connection but when i power the Arduino board from the 9v battery, the LED sets on for 2 seconds then it starts blinking eventually faster.
I mean that the line follower is not the problem cause it works perfectly with the USB connection.
Any reason for this?