Everything from the lesser key is a circuit diagram anon. This one looks like part of Teslas "death ray" defense shield.
Those could be waveguides, sure, but my interpretation is that they are a really, really big ground. Teslas stuff, all high voltage stuff needs excellent grounding. Look at his patent diagrams and you will see what I mean.
Demons are a differnt thing entirely, and this would not bind them. The right radio frequency will chase them right out of your area though… and the wrong ones will let more of them through.