These radio beacons are standard equipment onboard Federation starships and are capable of transmitting automated warning messages to send other ships away should a ship and its crew become dangerously contaminated with a plague or other infection. The U.S.S. Lantree NCC-1837's quarantine transmitter was activated by the crew of the U.S.S. Enterprise NCC-1701-D after the entire crew compliment died from exposure to deadly antibodies from the Darwin Genetic Research Station.