My company is using the ReSpeaker 2 board as part of a hardware project and have run into some troubles during our FCC class B certification. We’re seeing a large spike of EM noise 1t 84.006 MHz and some additional noise at approximately 300 MHz. If I unplug the board, removing power to it, the noise is no longer present.
Is this a known issue? If so, has another board design been released that might address this, or could it have been addressed with a software update?
Any pointers much appreciated, this card is critical to us and we would love to use it but it’s blocking our FCC approval and I need to find a solution.
We found the source of the ef noise, our speaker wires (2 sets) was acting as an antenna and radiating noise. A ferrite core for 1 MHz was added and solved this problem.