I am installing a IOSD and a video transmitter on my phantom 2, I allready have a gimbal H3-3D with the anti-interference board do I leave it in or remove it when installing the new parts ?.   do I still need it

well, it depends on you. its lilke a noise filter for your gimbal. Otherwise the gimbal may twitch from time to time or i should say could. My old H3-2D did that from time to time during flights

If you are using the H3-3D gimbal still you should keep it.

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