|
Diodes are electrical components that only let electrical current flow in one direction, the way a check valve does for gasses and liquids.
1N4001 rectifier diodes are easy to find (try radio shack) and can handle up to 1 amp of current, which should be fine for the MPGuino.
If you look at the diodes, you'll see one side has a stripe. You want to connect the striped end of two diodes to the positive power supply lead of your MPGuino. The remaining end of one of the diodes goes to the positive terminal of your 9V battery, the other remaining end goes to your car battery positive connection. The negative of your 9V goes to the MPGuino negative (ground) power connection along with the existing car connection.
|