Tracking a rotating item

Hello,

I will be conducting an expierment where I will be making voltage measurements on a rotating platform.  Duruing the expierment, I need to be able to document the voltate when the rotatin is at 4 loations 360 degree, 90 degrees, 180 degrees and 270 degrees.  In my mind, I see a product on the computer screen and printable where there are 2 graphs running in parallel.  A number 1,2,3 or 4, would indicate which direction is noted on the screen and the ability to see the voltage reading of the expierment above.  Obviously the voltage reading is a separate instrament.  My question is how to best make this work wiht the T-7 pro?  I was thinking of using a magnetic pick up on a rotating stage and 4 magnets on the outside of the rotating area.  Is there a way to make this work or is there a better way to set this up?

Rene Steinhauer