Over the years I've a Radio Shack 1/2 wave GP, a Ringo, an original Star Duster, an Antron 99, although I'll never figure out WHY!!, the Sigma and now the 2008. I kept the ball on top and also used a piece of hear shrink tubing on it. I rarely tune below 11 meters so I tuned mine up to about channel 35 or so. It gives me the range to really go upstairs when I want.
As a side note, I can't tell you why cuz I'm not a theory guy, but I have my radio, a random length jumper between it and DX-500V, a shorty jumper to a Daiwa 901 meter, through an old Johnson LP filter, and then the antenna. Seriously, I can tune well below 11 meters, all the way up past 27.800 or 27.900 and stay below 1.5:1. I have verified this on three meters ranging from the Daiwa, to the Radio shack to the Paradynamics.