You should always keep every component of your ignition system and radio system separated by at least 12 inches or as much as possible. Never have any metallic object in that 12 inch isolation area including a metal pushrod to the engine and especially a throttle servo. This advice holds true whether you experience interference or not on the ground or if someone else tells you that it's BS because they have gotten away not doing it. It will catch up with them one of these days. Dan.