Yes, it did put out 94 mW into 50 ohms for 100 mW input; an efficiency of 94%. And this is not at all unusual for that circuit. I have a scan of the original article, which appeared in EDN magazine, but would have to ask for copyright permission before I could post it. The article might be available from a good technical library if you have access to one. If there is interest, I will dig it up and give you the issue, volume, etc.
My design included a highly efficient output matching network also. I used large B&W miniductors for the impedance step-up. To prevent any radiation from the coils, they were mounted inside a large steel rack cabinet that was screwed shut tightly. You could draw a spark from the antenna terminal! I think the same is true for the Rangemaster. No one has ever proven it but some have suggested that the Rangemaster has a Class E PA also. In any case, it is a "class act" for a Part 15 AM transmitter!
One reason I don't post this information on Part 15 is that the board owner got all hot under the collar because I posted some links to enforcement actions. I think they are important to review, whether you are a licensed or unlicensed broadcaster, because they provide information about what the FCC considers acceptable (or not). But it's his board, and he didn't like it, so... Anyway, there are a number of professionals on this board in addition to the hobbyists, so it makes for lively discussions.
Part 15 operation has lots of possibilities and I, for one, am optimistic about the future.
