Great info Matt --
From what I recall, the county reduced the number of Battalions some time ago (true?) and they may have some affect on which set of talkgroups used.
I've always sensed that the battalions would be assigned the zone based on their battalion number (i.e. Battalion 1 boxes on 1-2, etc.).
Do you know if this is true and standard?
Seems like the others (at least from listening) become "overflow" should there be multiple incidents occurring (I think I heard 4-6 incidents on these groups back in the spring - even if for short periods until the assignment was reduced).
Given the shear number of fireground talkgroups, I had problems trying to decide what to put in various zones of the G4/G5. I had one zone for all fireground but had to limit it to just the first few in each zone (1-2, 1-3, 1-4, etc.) on order to get them all in (and since you rarely seemed to hear the higher numbers used). I also created zones for each group but of course there are more than you can get into a zine 8 position zone on a G4/G5. A conundrum.
I recall conversation in the early days of the county P25 system and why all of those talkgroups are really needed.... I suppose it is cheaper and easier to just do it early rather than coming back later and making alot of changes.
Baltimore City was nice and easy -- a knob for all fireground and then 1 for each of the 4 fireground groups....
When I started in 1999, there were five battalions. Not long before that it was reduced from six to five. Shortly AFTER that (maybe 2001), they went from five to three battalions, and implemented on-call battalion chiefs for major incidents or overflow, as a cost-saving measure. The argument for having only three battalion chiefs for a 610-square-mile county is that most career apparatus are staffed with a captain, who can adequately command an incident until the arrival of a BC.
The extremely overwhelming number of tactical talk group sets and expansion groups within those sets stems from the system's design, which was fast-tracked after the Amtrak disaster, and based around an (at that time) extremely progressive command and control structure and the possibility that battalion chiefs might eventually be added, which obviously never happened. The original STX radios all had full numeric keypads, and the talk groups could be instantly selected by punching in the talk group's one- two- or three-digit number (if you wanted EAST 3, you punched [SEL][3][SEL], if you wanted FG 32, you punched [SEL][3][2][SEL], if you wanted EMRC 221, you punched [se;][2][2][1][SEL], you get the point. So the now-cubersome issue of navigating such a large number of talk groups using a zone/channel configuration wasn't a problem.
I had HOPED that when the radio system was upgraded, the powers that be would reduce the number of tactical talk group sets to match the system's capacity and the department's actual realistic needs. Perhaps five sets of five talk groups would've makes a lot more sense. And more realistic based on the system's voice channel capacity.
The model for assigning talk groups is SUPPOSED to be:
Battalion one, first incident TAC12, second incident TAC62
Battalion two, first incident TAC22, second incident TAC52
Battalion three, first incident TAC32, second incident TAC42
The rest were assigned as overflow at will without any specific model.
I have no idea if its still followed, since the chief's numbers don't even correspond with their assigned battalions. And there are zone-specific talk groups that have to be used in site trunking.
If you want to hear about 98.5% of the good action in Baltimore County's FD radio system, program in DISP, CENTRAL, EAST, WEST, TAC12, TAC22, TAC32, TAC42, TAC52, and TAC62, and you'll be just fine.
