[Al Skierkiewicz]

Don,
Magnetic fields will have very little effect since they are not moving. The fields are stationary. The brush noise from the motors may prove to be a problem but only time will tell. Try routing the motor leads away from your RC and PWM cables or at least at right angles to the other wiring to mimize crosstalk. If you are having problems that can't be explained by anything else, it could be the brush noise. Brush noise is a high energy RF emission that is generated by the motor brush leaving a commutator segment. In the open motors like the FP you can see the sparks as the motor runs, which are the source of the noise.