EagleTree erratic RPM readings

[BrianG]

This might be a bit complex and take a little math to figure out, but here goes. Add a diode to one lead, and another diode to the other lead, but reversed. Then, add a capacitor between the two. The diodes keep the cap from messing with the ESC EMF feedback signal, and the cap helps filter the PWM pulses chopping up each phases. If done right, the ET will see cleaner signal indicating when each phases is firing, but not the pulses. You would have to know the PWM frequency to size the cap so it filter the small time between PWM pulses, but not the whole commutation signal. If that makes any sense...