I am curious.... I always thought that the mast must be attached to a section at least a quarter wave distance below the quarter-wave section of the jpole... I noticed yours extends all the way up inclusive of the quarter-wave section.
I think you may get a better reception if you extended that pole above the mast at least past the quarter-wave split.
I may be totally wrong, but I thought I read that the lower section of a jpole must be equal or greater than the quarter-wave length itself, and the mast must attach there below the quarter-wave breakout.
Heck, if anything, it will get it higher in the air