oomwat
Banned
Ironically, they do seem to be a way for explorers to know when they're getting close to a distant star.
It seems like the spawn rate of signals drops to zero when you're out in the void... but the moment you start dipping into a gravity well again, they start popping up. But maybe that's just me.
It's nothing to do with the gravity well (well not entirely 'nothing), but more to do with your speed (which, ok is related to the gravity well but hey) ... IIRC they are randomly spawned at a distance which is related to your speed - hence by going at 30km/s they pop up right in front of you - when you're doing 1800c they're bloomin miles away, so you never see them.