Hi David -
Thanks for responding to my questions. I agree with the way you have your scanner set up, but I think you might be confused about the radio system architecture.
The various sites (typically called "systems") that Pinellas County operates use simulcast technology. In simulcast, multiple tower locations (typically called "sites") all transmit on a given frequency at the same time. This approach, which is very common for large radio systems, provides for much improved mobile and portable coverage throughout the system footprint.
As you might imagine, if all the Pinellas systems actually transmitted from only a single location, the system talk-out coverage would be very limited... especially in medium and large buildings and locations distant from the transmit site. The radio system in Broward County, with which I am very familiar, also uses simulcast technology to enhance their county-wide coverage.
In addition, each of the Pinellas systems actually appears to target coverage for certain general areas. For example, the Ridgecrest system sites are scattered throughout the county in order to provide county-wide coverge, while the Toytown system sites appear to favor the St Pete area. If all of the systems provided the exact same coverage county-wide, there would be no real need for separate systems.
In any case, after researching the Pinellas site licenses, it appears that the simulcast transmitters associated with the Ridgecrest system have been removed from the site closest to me, and that is likely why I can no longer receive the Ridgecrest talkgroups as well as I once could. This might be part of the eventual P25 system build-out, since there IS now a transmitter near me (actually several) that are associated with the P25 systems. I guess we'll all have to wait to see how it all shakes out once the changes have stabilized.
In the meantime, apparently I won't be listening to any Fire talkgroups until they switch to P25 or I get a bigger antenna!
-JK