i got a distress signal out in the wastes when i activated some radio beacon

it was of a woman saying she was in a train car etc

i searched all the train cars nearby but couldnt find anything or anyone. except a single ghoul

was this just a flavour piece or is there actually a person somewhere?

Probably was, about 100 years ago, the Ghoul may be her.

I had the same problem too. Not sure where the ham radio / distress signal is coming from. I did find the body of a dead woman in the building by the bridge just next to the train tracks. I had to take a trapdoor down. Maybe it was the same one?

Most of the beacons in Fallout 3 are for things that happen years prior to you leaving the vault, and are just mini set pieces that seem to have a story that played out years ago associated with them for you to decipher for yourself.

I suspect its more of the same here.