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
Step 1:
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.
Step 2:
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.
Read more: Faire une Pile 9 v DC alimentation
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