Since an end fed wire is the best antenna that I can have at my location, I'm trying to understand better how it works, so that I can hopefully improve its performance. It does "work", but the term is relative. It kills my computer USB keyboard sometimes, which I believe is due to common mode current. Subsequently, I thought I would implement a 1:1 unun common choke, but I don't know where. I read online that a good place is between the radio and the 9:1 unun, right before the 9:1. In other places I read that no, that's not a good place, because by killing the common mode current there, it will also impact the "useful" current. Or something like that... I'm still drinking from a fire hose. Others say to use a tuner right before the 9:1, and at least a radial. Maybe use additionally the 1:1 common choke at the radio. I understand that the coax becomes part of the entire setup, and I would like to eliminate that, or at least minimize the effects. I would appreciate any input.