The mixmaster is a good tool for analysing spark on multiple cylinders for upto 12 cylinders where you could only do 4 at once with the 4 channel scope.. The way in which the Mixmaster works is to give a comparison of the spark accross all cylinders. It does not give scaling i.e. if your peak KV is 27KV you would not see it like this. You would see all (for example 6 Sparks) as a parade and you could determine which spark was poor in comparison to the others by using the trigger signal output on the Mixmaster and knowing the firing order of the engine.
The Mixmaster has a Maximum Input Voltage of 4.0 Volts on the BNC therefore this is why when you look at the scaling it does not really show the KV in terms of maximum output though. In terms of maximum KV and the Secondary Pick up leads, these are 10,000:1 so 20 kV would be 2 Volts, the Mix-master can use 4.0V input therefore you could look up to 40 kV.
I hope this helps to answer your first question and allow you to understand why the KV values dont really look like the values you would expect. I will look into a software probe for the Mixmaster though to try and make it easier for you within the Automotive Software and I will attach it to this forum post.
In terms of the hardware though. I dont understand why the Mixmaster would affect the Wireless card in the Laptop as it only gives an output signal to the scope through the BNC. In terms of the software and scope they perform perfectly normally and just represent the signals given off from the mixmaster as if you were looking at spark thorugh the secondary pick up cable or COP probe or any other sensor or actuator test.
Lee - Automotive Technical Specialist