EDT9 help

[Cjmbgrfd]

evening everyone. I'm hoping one of the experts floating around here might be able to give me a better rundown on the edt9 tach than the factory instructions did. Specifically the function issue. I feel like the readings are not entirely accurate the way I'm using it now. I think I want it set to 1/1 and I am currently running the small antenna would I be better off going to the longer one?