Re: Finally.
No, the phone companies are not on the hook as long as they don't transmit power on the wrong frequencies. As long as they stay on their allocated frequency without sidebands, they're fine with the FCC.
What's not fine is an altimeter that doesn't properly filter out neighboring frequencies. And you can tell from the FAA's list exactly which planes carry such defective altimeters. Bad new for the altimeter makers concerned - it's their product at fault.
Biting the hand that feeds IT
