In the latest issue of Mandolin Magazine there is an article about Mann & his electric Mandolins. In the intro McCarty lists players of electrics & acoustics. He lists Jethro with the acoustic players. If there is any player with a foot in each camp it's Jethro.
Certainly Jethro is an acoustic player par excellence. His trademark acoustic "Red" A-5 is certainly part of his image.
Yet, in an old Mandolin World News article Jethro claimed to be a big supporter of electric Mandolins, got one as soon as they came out, and bragged his Electric F-5 was one of the best. I can attest it was really cool. I did get to pick on it a couple of times. He used it exclusively on his "Jethro Burns Live" & the Venuti LP. He also used it on a couple of trax on the Jethro Burns LP. I saw him play it live on several occasions.
Now there are pix of Homer & Jethro using Fenders. Jethro said was an endorsement deal. They got them free so Jethro had a couple around. He said they lost the deal because they had to do a Jimmy Dean Show & they were supposed to walk through the audience which they couldn't do with unamplified Fenders. So they used their regular axes. Fender didn't like it so their relationship went bust. That's the way I remember the story. Regardless, Jethro wasn't crazy about the Fender, not because it was electric,it was the single strings he didn't like. He said he thought it "would ruin his technique." I think there are a couple of trax on "Jazz from the Hills" where he uses the Fender.
I know there were occasions later where he was playing his Washburn wired up instead of his Electric F-5, but I think that was as much of the endorsement issue as much as anything. That is speculation on my part. I wish he had used his regular electric on the Austin City Limits Mandolin show with Tiny and Gimble. I think the wired up Washburn sounds kinda thin. I would have liked to hear the three of them all electrified.
Jethro, armed with his Electric F-5, was dangerous. With an acoustic, he was equally a killer.