The distress pulser is a junk/quest item in Fallout 4.
Distress pulsers send out distress signals to nearby areas. They are a specialized piece of equipment with a long-lasting battery and powerful enough to cut through heavy interference; useful if someone wants to, say, mark a location for recovery in a heavily irradiated area.
- One can be found in the National Guard Training Yard in the room where Knight Tara Astlin made her final stand.
- One is received from Scribe Haylen at Waypoint Echo during Liberty Reprimed, used to mark Sentinel site Prescott for recovery.
- The Sole Survivor: "Why use this Distress Pulser?"
Haylen: "Unless you could locate an entire radio station within the Glowing Sea, there's no way you're going to be able to send out a regular signal. Luckily, the Distress Pulser's ping cuts right through the interference and we'll be able to hear you as long as we stay close to the frontier. Look. I know you've been through the Glowing Sea before, but remember to keep an eye on your Geiger counter. If you don't, the radiation will cook you from the inside out. Good luck, Knight."