Fixes the critical lack of honking in Factorio. Two means go and one means stop.
Now with hotkeys! Press J while riding a train to toggle manual control, press H while in a locomotive to honk, and Shift + H to use the secondary honk (secondary honk is 0.18 only).
Audible distance, volume, and honks for specific occasions are configurable in-game using the mod settings menu.
"Automatic" mode for the Honk! key chooses sound based on whether or not the train is moving (0.18 only).
Trains repeatedly honking while waiting at signals appears to have been fixed as of Factorio 0.17.37