Any scanning history around Linn and Benton counties?

[far342]

As I'm newer to scanning I don't really know much history about the departments around Linn and Benton. I'm just curious if anyone here who's been scanning this area for a long time has anything they'd like to share. I'm mainly wondering about things like what years did certain departments go digital or anything notable that's changed along the years with the way departments operate their radios. Did any Linn County departments ever use 12-codes like Benton County does? Has Benton County always had regional dispatching or is that a newerish thing? Back when Adair Village had it's own police department were they on the same regional dispatching as the rest of the county or were they on their own? Anything would be interesting. Thank you