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- Now we're going to add one of the 4-pin sockets into P4. These pins provide test points where you can connect a voltmeter and ammeter across the power supply to take test measurements.
- Find the footprint for P4. It is next to where you installed the power LED.
- Install the socket onto the board.
- You will need to tape this component to the board. It does not matter the orientation of this part.
- Now solder it into place. The pin on the right in this photo is a ground pin, and may be a little more difficult to solder.