EMI from Controller

[JedidiahStolzfus]

My helmet is able to connect to my phone via bluetooth.  The first time I tried it just to play some music to see if it worked, every time I pedaled, the music would wash out with digital static.  I figured it was shitty circuitry on the controller or motor's part and figured I just wouldn't use bluetooth.
The other day I thought maybe putting a ferrite bead on the motor cable might stop the EMI.  I dug one out of my ferrite bead drawer and put it on then went for a ride playing music. 

The music played perfectly now matter how fast I pedaled.  I thought "success" the ferrite bead wiped out the EMI.  Then I remembered that I put the 35A controller on the bike since the last time I tried this.  I stopped, and took the bead off and rode home.  No interference.  The controller supplied by RAD apparently produces the EMI all on it's own. 

[Radio Runner]

Interesting. The rad supplied switching power supply wipes out entire bandwidths when I charge the battery that?s for sure.

[JedidiahStolzfus]

Interesting. The rad supplied switching power supply wipes out entire bandwidths when I charge the battery that?s for sure.

Which, if that device were made in the US, the FCC would never let it be sold because it's interfering with communications.  But since they come from china, who gives a fuck, the FCC doesn't.

I've seen USB chargers in cars wipe out the FM radio band.