[RodB]

FM is capable of modulation to 15kHz (beyond my range) where AM is good to about 5kHz. But there are so many differences, pointing to any one is difficult. I'm sure Armstrong was just as fascinated as we are.

BTW in my senior high school Radio TV class we used to identify a television chassis by how strong the horizontal oscillator sounded. At 15,750 CYCLES we would zero beat two chassis sitting next to each other. Goofy kids!