I built the Signal Interceptor and I also have it powered up just my game won't continue just keeps telling me to power it up and i have tried searching the web and tried every method i came across but it still won't complete. Does anyone know how to get this quest to work? I did mine with the minutemen faction if that helps any.

Try to align the buildings , the platform should be put under the tent-looking like structure and you better have the console in front of it, just to be sure.

To me it worked without problems all the times i did this quest, after i realised how to build it.

Check with the quest stages in your Pip Boy to ensure everything is ticked as completed, if not re-do the one that isn't.