A device like this actually appears in the plot of Matthew Reilly’s Temple, tho in the book the nuclear material used was from a meteorite…still tho it was basically sundial

https://en.wikipedia.org/wiki/Temple_(novel)

I have seen Bias Tee injectors for up to 50v@1.5A, thats enough for a decent output booster. But yes in reality 99% of those where used for preamps in analog TV/Radio Rx