This is pretty interesting. If you look at John McClain's radio in the beginning of the movie, when John McClain is going to pick up his daughter he uses a radio that shows a frequency around 144MHz. The amateur radio 2 meter frequency allocations are from 144MHz to 148MHz. As a police officer, John McClain would not be allowed to use this frequency. Also, a VHF signal from a mobile radio would not reach New York City from Washington DC. I'm not sure if they put this in there because amateur radio would "survive" this kind of attack or if it was simply a mistake. Let me know what you all think!