Battery Powering Arduino Uno
Created on: 8 August 2012
This video shows how to make up a cable to connect a 9V battery to an Arduino Uno. A 2.1mm barrel connector is soldered to a battery clip with the positive (red) wire connected to the centre of the barrel connector.
The pre-loaded blink program starts flashing the on-board LED on and off after the battery is plugged into the Arduino.
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The voltage of the battery will be about 9V if six 1.5V cells are used in the battery holder. If rechargeable cells are used, the battery will produce about 7.2V.

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