So... I've never used an oscilloscope before so this was kind of fun.
Testing steps:
1. Measure RPM of test motor while connected to my Motolyser II to verify accuracy of the rpm that the device reads.
2. Couple test motor to the motor we are wanting to determine the Kv
3. Ground one phase of the DUT and probe another with the oscilloscope
4. Take measurement of RMS voltage
5. Note the RPM of the test motor
6. Divide RPM of test motor by the RMS voltage of the DUT to find Kv of the DUT
7. Hook the DUT up to the Motolyser and get its measured Kv from it

I used a USGT motor as my test motor and an R1 v21s 21.5 as what I was trying to find the Kv of.
Kv from experiment was 2659
Kv from the motolyser was 2568

Now, the experiment was crude but fun. Also I expected a nice sine wave on the scope and got a jagged sine wave. Tried multiple motors with the same results. I am going to have to figure that out, but like I said, first time using a scope.

Now I would like to test a SKY RC and a Tunalyser. But...


EDIT: I ran the test again but this time using DC coupling on the channel and the Kv was almost spot on with the Motolyser. 2566