How to make each train go to a different (same name)station?

[mrvn]

A chain signal going red by a train blocking the adjacent block will not cause a train to repath. A circuit switched signal, even if it's a loop back "read signal, set read signal" will do that.
See viewtopic.php?f=49&t=46623 for similar issues.

No, but disabling the station will cause a repath. The chain signal is just to prevent the train from getting stuck.

[SpeedDaemon]

Having only one train driving at a time, even if it is per item type, is a no go. The question wasn't about how to make each train pick a different station at the start but how to make them keep trying till they get it right. And for that:

No need to switch signals. A chain signal does this naturally. The important part is to have a chain signal before the branch to the station to make other trains stop where they can still go past the station. And a chain signal after the branch so other trains can actually pass while a train is at the station. No real signal on the branch before the station or a second train can enter the branch.

You might still benefit from only allowing one train of each type to leave the waiting area every X number of seconds. It will still limit throughput a bit, but it might limit it less than having the entire waiting area empty out immediately towards one station then having to turn around and go back across a large map.

[mrvn]

Having only one train driving at a time, even if it is per item type, is a no go. The question wasn't about how to make each train pick a different station at the start but how to make them keep trying till they get it right. And for that:

No need to switch signals. A chain signal does this naturally. The important part is to have a chain signal before the branch to the station to make other trains stop where they can still go past the station. And a chain signal after the branch so other trains can actually pass while a train is at the station. No real signal on the branch before the station or a second train can enter the branch.

You might still benefit from only allowing one train of each type to leave the waiting area every X number of seconds. It will still limit throughput a bit, but it might limit it less than having the entire waiting area empty out immediately towards one station then having to turn around and go back across a large map.

Oh indeed. Yesterday I tried it in a sandbox with 10 trains and all 10 left when I enabled one station. Horrible congestion on the railway. But I don't think allowing one train every X seconds is going to work. That seems horrible fragile. With a large waiting bay and minimal signals the congestion on exit will limit the trains per minute already and that doesn't help at all. They still leave.

Instead I'm thinking of using a token system. Every station that wants a train sends a pulse to the waiting yard. At the yard for every pulse a token is taken out of chest A into chest B. And if there is an item in chest B a train is allowed to leave and one item put back into chest A. The drawback is that you need to run a signal wire from every outpost to the waiting yard.

Hmm, thinking out loud: Train station enable/disable transmits without wire or delay. Maybe one could use trains to transmit signals. But then every train stop would need 1-2 extra train stops and trains for signaling. They would have to be real far away to be cheaper than signal wires.