system
Given the following post, respond as if you're commenting on Reddit:
human
eli5: When driving into a tunnel, why does it take quite a distance in for you to loose radio signal but you don't get it back till right at the exit, not a similar distance to the exit as you lost it from the entrance?
gpt
It mostly has to do with the way radio receivers work. 

It uses something called a *phase-locked loop*.

Basically, once your car has found the signal it "locks" to it which makes the signal clearer even though you might get a few disruptions here and there. This is why you are able to keep hearing the station even after you are in the tunnel a bit. The signal is very weak but your car knows what to do to boost it. 

But after you completely lose the signal you are going to need a good strong signal to re-lock to the station.