A bit of history for anyone interested ............
The first Roadtrek Etrek video from 8 years ago or so actually showed a small AC generator unit. It was a Fabco Power Mite. Maybe that's how the phrase Under Hood Generator came to be used. The Power Mite, generating AC, would actually be under the hood.
I am not aware of any RT that used an actual under hood AC generator though.
The UHG common to RT's consists of a DC alternator and regulator under the hood and a large inverter located somewhere in the coach.
Here's an old topic that includes several example of under hood AC generators:
https://www.classbforum.com/forums/f...-etc-2544.html