Next, we see the eastbound signals at the west end of Big Chimney change as the dispatcher lines the route through Big Chimney on the main. Note the signal at the west end of Big Chimney initially displays Approach. The turnout here is lined for the main and the turnout at the east end is lined for the siding. The Approach signal tells any eastbound movement that the next signal will be Stop. Once the dispatcher lines the east end turnout for the main, the west end signal displays Clear for the main as does the east end signal. As the eastbound freight heads toward Big Chimney, the eastbound signals drop to Stop.
Next we see the way freight moving past the local in the hole at Big Chimney. Note that the westbound home signal for Big Chimney on the hill drops from Approach to Stop as soon as the eastbound freight enters the block at the west end of Big Chimney.
Once the eastbound has cleared the west end of Big Chimney, the dispatcher lines the turnout for the siding and the westbound local receives an Approach Medium. The crew of the local know that they have at least two clear blocks ahead.
As soon as the local hits the block with the turnout west out of the siding, the signal at PN Cabin drops from Approach to Stop.
Note that once the local passes the west end signal for Big Chimney it changes to Approach. The turnout at the west end is still lined for the siding and it is unoccupied and the east end turnout is still lined for the main. An approaching eastbound would know that the next signal it encounters would be Stop.
In some future post, I'll detail the preparation and planning that took place in order to get the signal system to this point. But for now it's back to making resistor wheel sets... for every car on the layout.