I monitor the Mass State Police Zone 3 (Bristol County). Radio is SDS200. My question is I only use the Bristol County site frequencies, mainly because that site is the only one I can receive from my house. It appears the TALK GROUPS from other areas OVERLAP. In other words I can hear BAPERN talkgroups, Boston tg's, etc. I am wondering how much overlap exists. I am sure I wouldnt hear anything from western Mass or even Worcester County. I live in Cranston RI. I can hear Bourne FD from the Cape on the same Bristol/Plymouth county site. Even Provincetown. But there is another site for upper-mid cape but I can't hear those freqs....too far away. I don't understand how the TG's work as far as should I just program ALL of the Mass state PD TG's. Maybe exclude western mass. I never bothered to try cause when I got the radio I didnt realize how much overlap of TG's there was.