Making a 9v Battery DC power supply
Rather than use the USB to power my Arduino board with a handy trip to the electronics store with some more knowledgeable people than I, I have constructed a 9Volt DC power supply.
Taking a 9 volt battery, a 9v battery holder and a 2.1mm coaxial DC jack (positive tip) I have quickly soldered a portable power supply and better yet it works! (You will also need solder and a soldering iron).
DC Power Supply Components
2.1 mm coaxial DC jack
PP3 9Volt battery
PP3 9Volt Connector / 9Volt battery holder
Trim the wires on the battery box and make sure that theres at least 5-10mm of exposed wire. Unscrew the jack, take the housing and thread the wires through.
Connect to positive (red) wire to the base of the pin and solder, connect the negative/ground (black) wire to the tall pin and solder. Making sure that there is no connection between the two.
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