All public safety talkgroups go with all towers now....
Not entirely correct. Not all agencies have ALL the towers in their radios, therefore their radio will never roam to a certain tower. For example, Cornwall only has Beacon and Schunnemunk programmed in their radios. So on their BASE 4 talkgroup, they will only come over one of those two towers. Useless programming their talkgroup in and trying to monitor them on Arden..you will hear nada, Now, when they switch to the POLICE 800 talkgroup after midnight for County dispatch, they still only have Beacon and Schunnemunk in their radios. BUT, the POLICE 800 talkgroup is linked on all the towers so you will hear them over Graham or Arden as well as Beacon and Schunnemunk. However, if the Cornwall unit travels out of the coverage area for Beacon or Schunnemunk, they will not roam on to any of the other towers because they are not programmed in.
On the other side, the Sheriff's Office has all the sites programmed in their radio with several PDs that dont use all the towers (like City of Newburgh PD who just uses Beacon) City of Newburgh PD's channel will come over other towers if a SO radio roams to that tower and has the talkgroup in their scan list.
Lastly, some talkgroups are full time links while others are affiliation only. For example, Woodbury PD always comes over Arden, Schunnemunk and Beacon even if all their units are only affiliating on Arden and Schunnemunk. Town of Montgomery I think comes over Beacon, Schunnemunk, and Sam's Point full-time. There are several others.
The reasoning behind this is so units don't get busy signals due to limited bandwith. Why tie up a frequency on Graham with City of Newburgh traffic when they are on the other side of the county and the site only has 3 frequencies available for use at one time, one of which is a control channel.
