I thought there were two identical spheres. One was the control and the other was the active one. There were in a bath and the entire setup was open for inspection during the seminar. Afterwards, he cut open both and they were hollow although the active one had hydrogen in it.
The hydrogen wasn’t continuously fed, I think the sphere was charged and that was it.
While it would be easy to fake, I would think the attendees would have seen something and from what I remember, it ran for a long time.
Cravens was never going to power a turbine but it was a proof of concept. That is why if I knew calorimetry, I would get ten nanors and set them up to see if there’s anything there. The electronic control circuit is simple and if you use D/C, it is simple arithmetic to calculate power in. I have no idea how to determine how much heat output it creates or how you compare the heat output with the electrical power input. It would answer once and for all if there is something there.
Your recollection is correct. That is precisely Cravens NI setup. Both spheres were immersed in a heated sand bath and their temperatures monitored.
“Afterwards, he cut open both and they were hollow although the active one had hydrogen in it.”
According to Craven’s report, he only cut open the active sphere and it wasn’t hollow.