RF interference

[WAXER128]

Just wondering if motor interference is more prone to AM or FM freq's? Same size and set-up of capacitors for AM and FM?
Thanks

[patmat2350]

Worst: AM
Much Better: FM
Way Better: FM/PCM
Top o'Line: 2.4 GHz

[Ghost 2501]

remember when you drive under power lines listenning to the radio, notice how AM/LW/MW all crackle, yet FM doesn't, its the same for RC