NYC _IS_ working on a new system - I know a guy who worked for DoITT and still works in comms for "undisclosed" agency (for his privacy) - They have had systems put in that totally failed, and there was some real fun with one of the radio companies (Hint, he has carried the new radios they are testing). I know he personally got his hands on some of the radios they are testing - on his OWN personal dime
They are looking at various brands of radios that go from 50Mhz to the 900Mhz band, all in one radio, that hand conventional, trunking, P25, plain voice, etc
Lots oh fun
I mean, FDNY tried what, 2-3 times to upgrade JUST their own radio system, and it didn't work
FDNY has a real "interesting" way their radios work/worked - the idea was that dispatch was on 4 frequencies (SI and the Bronx shared), and that the "fireground" frequency was common, but the radios were low power, and had very limited range. The idea being that it was rare to be fighting two fires close to one another, and geographic seperation would keep 2 fires from conflicting, but when you rolled up on a fire, you WOULD be on the right frequency. The PROBLEM comes when you get into a highrise fire, and the radio power is low enough that you can't talk out (which is why certain buildings like the WTC have/had a repeater that could be turned on), and also when you get 600-700 firefigters all on one fire, the radio turns to chaos. The OTHER fun was when they tried to go digital - a certain radio company that will remain nameless sold them on "it's always clear, no static" - what they never mention is that with plain old unencrypted analog, when you are borderline, you can still make out say 50% of the transmission, and get some clue/know that there was a tranmission, where with digital, it's 100%, or NOTHING