A combination long-range communicator and signal transponder. The commlink beacon is a very sophisticated emergency signaling device. The internal transponder monitors common emergency search-and-rescue channels (one at a time). When traffic is picked up on this channel, the device simultaneously emits a shrill warning tone to alert users to the possibility that help is at hand and transmits a coded distress signal under a traditional GK (Gashimeku Kalariin, the Vilani SOS). Some more expensive models have provision for auto-repeat voice, video, and/or data, instead of the automatic code signal. In either event, the commlink beacon serves as a means of establishing contact when there is any search being mounted within 500 kilometers, and then it serves to continue communications after that initial contact. With a size 2 Ambient Panel, it can operate indefinitely.
“Traveller 5.10 Core Rules Book 3 : Worlds and Adventures”, Miller, Marc , Far Future Enterprises