Darrel... i don't think it will be revealant to be 50% or not... it's all about pulse/miles after all.

In the good ol' time we installed 2 magnetic sensor on the drive shaft as a VSS generator. using that... no way you could have a 50% duty cycle as the magnets where about 1 inch wide.

I should take a car ride here and record the VSS signal to see how clean it is... in case some want to know.