Simplest solution? Circuit network that links activity on unloading inserters to the station. The drawback is that I have never used the combinators ever beforehand, so I'm diving into this blind.
The plan is to have a very short resettable timer (about 2-3 fast inserter cycles long), that as soon as the rate at which the items are unloaded falls and fails to reset the timer before it reaches its limit, a signal is sent to the station to send the train off.
So far I managed to make a timer that can be set off with an item signal, but I have no idea how to make it resettable.
My efforts so far
Any help or advice from circuit network gurus is greatly appreciated!