Caravan distress frequency

Caravan distress frequency is a radio signal It can be received with the Pip-Boy after starting the quest Mechanical Menace.

Transcript
Jackson: "This is an emergency broadcast! Our caravan's under attack by hostile robots, and needs some serious help! We're just east of Wattz Consumer Electronics. If anyone in the vicinity can come help, now's the time! Ada! Loop this message!"

Ada: "Yes, sir."