I'm not familiar with the MPSCS system, but looking at it's page in the RR database I'd say it's highly unlikely you would be able to monitor both of these counties from one of them. This highly integrated system is a bit unusual though, as most states are still pretty fractured in terms of Public Safety coms. In my state, in one county alone, we've got State Police on VHF conventional, County Sheriff on VHF conventional, a city pd on UHF conventional, that city's fire on 800MHz analog trunking, another city's PD on 800MHz analog trunking, yet another city's pd is on VHF NXDN digital, county fire is on VHF conventional. And that's just one county.
Since your counties are 100+ miles apart, there is about zero chance your radio will receive a useful signal from the distant one. And most trunk systems are set up so the users' radio affiliates with a nearby site or simulcast system. You may hear its talkgroup on a neighboring counties' site, but four counties over seems very unlikely, even though it's the same system. That being said, it might be worth it to have this thread moved to the Michigan forum where someone who is familiar with MPSCS can possibly answer it.
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