ORIGINAL: All Day Dan
Speed, you have to assume that the ignition system, which includes the spark plug, has the capability to generate any frequency from DC to light and you better protect youself from it. It may not be at the frequency that you are transmitting on all the time but all you need is a few seconds of it and you're in. So, assume it's there and follow all your manufacturer's guidelines which are just good RF principles. They know best since they designed the RC system. Dan.
Dan, you may have misunderstood my post. I pretty much preach that you need to keep proper isolation between components. I simply stated my post as a question to hopefully open up some minds. Far to many people think that 2.4 is a cure all for any type of interference. Trust me it is not, I deal with antennas of all typs and frequency ranges for a living yet if the advise is not what one wants to hear it is ignored. Just as well, keeps the airplane manufacturers in China busy.