Yes, it was him who did a lot of the full scale museum restorations, i seen some pictures of him working on machines that large he had to crawl into the cylinder...
This is a really cool experiment he did and i tried to replicate it with my 1930s 0 gauge Hornby locomotive and an old British car heater motor i had lying around and hooked it up a tinplate model stemplant (unfortunately i don't have any pictures since my old cellphone did not had a working camera).
However, it of course works with most old type analog modeltrains and i think a regular bicycle generator may be enough to at least make the motor turn on a Small locomotive if one want to demonstrate it to children for example or are just curious like me...
I think it would do with an old radio as well if one use like a modern brushless motor as generator.
(We don't have those beautiful old signal motors, as he use in the experiment, anymore in my country but it has been on my wishlist for a long time...)
As he explain in the video it is quite simple; he made a breakout line from the stator magnet coil and hooked it up to a reostate (an old type variable resistor, but any potentiometer strong enough to handle the current will do) and also connected a few meters so you can see what goes on there and adjusting the reostate in order to synchronize the voltage output whan needed. This is actually a really good illustration of what goes on in a full size powerplant generator (like in an old water powerplant) of similar principle.
https://www.youtube.com/watch?v=P0Lutql7M3g
