[TenTec] Pegasus/Jupe Band Scope Questn

[Steve N4LQ]

What limits the speed of the Peg/Jup's band scope? When I used the Jupiter's bandscope it was fairly fast but when using it in Peg mode, it is really s l o wwww.
Is this the fault of the rig, firmware, comm port, pc processor, software (N4PY) or what? 
I want the sucker to really fly but I want to see it on the computer, not the Jupe's little green display. What would it take? Has anyone found anything that makes a difference?

Steve Ellington
N4LQ at iglou.com