I found this old ad for the Delco Light Plant, which let the farmer's wife do more chores using electricity such as churn the butter and do the laundry, even after it gets dark outside. So it's a win-win for the farmer. Not so sure about the farmer's wife...
The motor on the tripod stand they show in that ad belted up to various equipment is just like the one I have.
As for the shows I had gone to, Darke County Steam Threshers and Tractor show in Greenville Ohio and the Portland Indiana Gas Engine and Tractor show. The Darke County show has since split into two different shows, one for steam power and another for tractors and engines.
To put me fully into the gas engine nerd category I have an antique spark plug collection.!