Beaconing_from_above

You get home to find that one of your old amateur radio projects received something interesting. Who say's leaving old tech listening doesn't pay off? Looks like it's coming from an old CubeSat, how did it survive this long?

The flag is the four payload words, joined by single underscores, wrapped in STARPWN{...}. Submission is case-sensitive; the decoded message is uppercase A-Z and digits.