@Jonathan-Roberts said in Simple AC/DC Switch WeMos: @nca78 bummer. So I think 2 options... What if the Wemos is raised off the PCB. That would be almost 5/8". In your experience would that help? And maybe the best option, slide the antenna module straight down,. move the relay up and spin it around so the connections are on the outside edge. I'm trying to make this multi-purpose and allowing both headers to be fully functional to other projects. thx for the advise. 1 would help but not that much. It's already not a good thing to have the transformer just next to it on the side, so you should avoid blocking one more direction with tracks. I don't understand your necessity to have connectors available for something else on the relay that is too high to put anything on top ? 2 sounds like a much better option, make sure you have nothing right and left of the antenna when you move things around. The problem you will have with this layout is the USB in that situation... It doesn't sound like a great idea to me to use Wemos on this board especially for the relay part, it's just a cheap chinese relay with 3/4 components so why not just put them directly on you board to make the layout so much easier ? I have the feeling that you're trying to make things "easier" by using Wemos and its shields, but in the end you seem to lose more than you gain. And neither does it seem "safer" to use their relay shield as it forces you to have extra wires between main of the HLK and relay shield connector.