Note that a lot of "fusors" are actually "demo fusors", i.e. they run at too low energy to produce detectable fusion even if you did fuel them with deuterium. A

Note that a lot of "fusors" are actually "demo fusors", i.e. they run at too low energy to produce detectable fusion even if you did fuel them with deuterium. A "demo fusor" just produces plasma that looks similar without doing real fusion. This article is about the real thing, which is substantially more difficult to build.