I think Redstone's security and fire are digital and to some degree encrypted. Work hasn't taken me out there in a couple of years now, so things may have changed.
One thing I do recall, is sitting in a hotel on Martin and the Parkway, I very seldom heard anything on the scanner, not even a CC lock on. Now if I were up on University, reception was better. Although PD and fire were never very clear. This was on their new system.
I don't think I ever heard anything on either of the older channels and I had them programmed in the scanner as well.