I got this in Email from Bryan Holland (BHGravity)
At yesterday’s IAEI meeting, Treasurer Mike Looney brought in an interesting receptacle outlet found in a home built in the 1920’s. After some research, I was able to find some information on this receptacle. I thought it would be nice to share it with the group. The receptacle was manufactured by the H&H Electrical Company. In 1927, the company merged with the Arrow Electrical Company to become the Arrow-Hart & Hegeman Company. The company eventually merged with Cooper Industries, now Cooper Bussman. A picture of the product is provided below. The device is called a “Duplex Radio Outlet”. Notice the unique plug configuration of the top outlet. An ad from 1928 advertises the product as the solution for a “radio in every room of your house.” Radios could be “plugged” into this device to receive an “aerial” & “ground” connection to the exterior antenna on the house. The bottom portion of the device provided normal premises wiring power.
Bryan P. Holland, MCP Inspector / Plans Examiner City of North Port
I know them recepts. My last house had a couple of them (and probably still there). Being the town was and still is a fishing town, I'll bet you could find many of the old houses there still having them.
As someone who had an electric train as a kid, I doubt that it would be practical to send 5Volts anywhere in the house and expect to have any output voltage at all by the time it got to the wall outlet. More likely we will be sending 120V (or higher) to each receptacle, which will have a wall wart built into the box at each outlet.
BTW, McDonalds looked into those receptacles in the picture and it's just another good idea that's 'not ready for prime time'.
The vampire voltage/phantom voltage use could be eliniminated by incorporating a switch into the USB socket that only turned on the USB when something was plugged into the USB.
I don't think that would help much (I as I think most people would do is just leave the USB cable plugged in all of the time and only unplug it from the USB device) Maybe a sensor to monitor to see if the device is actually charging/Drawing power would work but of course cost more
Theres always enough room in the junction box.You just need a bigger hammer