Re: radio channel
If you have two brain cells to rub together you'd think this would be easy, but it isn't, especially in a big city like Chicago. It's so much easier to just keep using what you already have.
I wasn;t making any comment on how easy (or not) it might be to implement. What I was saying is that in the UK for at least a couple of decades emergency services have been using secure communications (TETRA, provided by the Airwave network) and I know that similar secure networks are used by these services in a multitude of other countries. It strikes me as odd that in the USA they're still using something so insecure for this purpose.