Back in the 90's when I worked for the Motorola outfit in Spokane we had what became known as "Firestorm" (1991). It spawned a HUGE job for our outfit. The various fire depts tried to loan out each other crews and equipment during firestorm, but nobody had foreseen such and the RADIOS WERE NOT COMPATIBLE. They pretty much "took over" the entire county fire radio equipment/ channels/ sites/ etc. and revamped, rechanneled, relocated some equipment, and bought some more, new and used, having the goal that someone with a handheld radio could talk on at least one fire channel anywhere in the county.
They did not quite meet that goal, but close. I spent a LOT of time reconfiguring gear at various radio sites from the N end to the S end of Spokane county
This was an incredibly complex project. For example, there were several sites where several radio receivers were listening to their respective channels, and shot their audio output down to dispatch at the pubic safety building in Spokane. These outputs went to what is called a "voter" which picks the best receiver signal and sends that to the dispatch consoles, as well as back out to wherever the repeater transmitter is located.
This audio must get from wherever the receivers are to the dispatch voter. This varies as some remote sites don't have the same facilities.
One such convoluted path, were 3 receivers up at Deer Lake MT near Deer Park WA. There was no audio link up on the mountain, no microwave, no fiber, no telco lines. So we shot them down to Deer Park via 3x dedicated radio links to a pumping station which provided an interface to fiber. The 3X receiver audio then made it's way over telco lines and fiber until reaching one of the county microwave stations. The county microwave voice/ data system operates in a big circle, so that if one station fails, some of the communications is still relayed via the "C" rather than the "O"
Now, finally, the audio(s) are relayed to dispatch via the microwave.
So for the receivers at Deer Lake, just for the 3 receivers, we imployed RF links, telco lines, fiber, and the county microwave.
Some of the transmitters were located at Mt Spokane --KXLY4 building which is a great transmitter site, and a poor receiver site, LOLOL (High power TV transmitters)
