Kirks communicator

Communicators are fictional devices used for voice communication in the fictional universe of Star Trek. In at least one instance (TOS episode Tomorrow Is Yesterday), they also serve as an emergency-signaling device/beacon. They allow direct contact between individuals or via a ship's communication system.

The communicator in the Star Trek universe surpasses the capabilities of modern mobile phone technology. It allows crew members to contact starships in orbit without relying on an artificial satellite to relay the signal. Communicators use subspace transmissions that do not conform to normal rules of physics in that signals can bypass EM interference, and the devices allow nearly instantaneous communication at distances that would otherwise require more time to traverse.

In Star Trek: The Original Series (TOS), communicators functioned as a plot device, stranding characters in challenging situations when they malfunctioned, were lost or stolen, or went out of range. (Otherwise, the transporter could have allowed characters to return to the ship at the first sign of trouble, ending the storyline prematurely.[1] )