John...I'm not missing any traffic and you debate programming methods that you don't understand.
I understand exactly what you're doing, and you're wrong about missing traffic, for the simple reason that in most systems, there is not a neat 1:1 mapping between sites and departments. Site coverage is planned based on RF propagation, not county boundaries. And the system programming that dictates which talkgroups are broadcast from each site follows the same principle.
For example, a small town PD near the edge of county A may mostly use a tower across the border in the county B because its location gives them better coverage. In that situation, if you have one instance of the system for County A and another for county B, you'll miss all or most traffic from Smalltown PD. Here's why:
When you're listening to the County A copy of the system, you won't hear Smalltown PD, because it's not normally broadcast from any of County A's sites.
When you're listening to the County B copy of the system, you won't hear Smalltown PD unless you:
- Program county A's talkgroups in county B's copy of the system. But that defeats the purpose of programming separate copies of the system for county A and county B. If everything for county A is programmed in county B's system, you've forfeited any advantage of programming multiple copies of the system.
- Turn on ID Search in the county B system. But then you will only see the talkgroup ID, and the scanner won't tell you what you're listening to, even though it could.
So to solve this, you have to either program a department that lives in county A into couty B's system (silly and counterintuitive), or you will miss traffic.
Another problem with your approach is that since RF propagation doesn't follow county boundaries, toggling sites by county guarantees you're going to spend more time scanning out-of-range sites than if you used Location Control. If you're on the south side of county A, that doesn't mean you can hear sites on the north side, and vice versa. Location Control toggles sites individually, irrespective of jurisdictional borders that mean nothing to radio waves. If set up correctly, when you're near the border of county A and county B, Location Control will activate nearby site(s) in both counties, but not the ones at the far reaches of either county, that you can't hear anyway.