>Your smartphone is a way more noisy electrical environment than your car. Cellphones are are certainly tricky, but in a different way than cars. In my experie

>Your smartphone is a way more noisy electrical environment than your car. Cellphones are are certainly tricky, but in a different way than cars. In my experience with EMF measurement and EMI compliance at Underwriters Labs, cars are uniquely challenging due to the relatively strong EMF generation from the huge number of motors, solenoids, coils other magnetic bits banging around and interacting with each other in hard-to-predict ways.