This not-quite-a-shield provides a barrel jack for the YUN, with a 5V LDO regulator and raises the board enough to put normal shields on without an issue.

Also included are two JST connectors and a prototyping area. One of the JST connectors is wired to the 5V input of the LDO and the other to the 5V output of the LDO. The prototyping pads are an experiment. A ground line and a power line run down the middle. The power line comes from the Yun’s 3.3V or 5V line and is selectable by jumpering the right angle connector to one side or the other.

NOTE: The silkscreen for this is not very good and may be refined in a subsequent version, if I feel like it.

NOTE: The slots for the barrel jack didn’t upload correctly. I routed mine out with a small drill bit, but I will probably fix this later with better features.