Photo Sensor

[Mr. Steve]

I'm trying to measure the speed of our shooter by mounting a photo sensor on the flywheel. A couple weeks ago I picked this up: QRB1134

http://www.junun.org/MarkIII/Info.jsp?item=14

And I'm looking at setting it up. I understand it has to be close to the wheel but I'm having trouble making it work. In fact, the only way I can get the value to change from a 1 to a 0 is shining a flashlight into it.

So I'm just wondering.

1) Is there anything I can do to improve this sensors operation?
2) Can I just buy something else that would work better? I'm willing to pay overnight shipping at this point if it means getting something that would work.

Thanks for your help!