This page contains information regarding Star Trek: Discovery, and thus may contain spoilers.
In 2152, while Enterprise NX-01 was docked at an automated repair station, Commander Tucker witnessed an entire transtator assembly replaced in fifteen minutes, whereas it would have taken his team a week to do so. (ENT: "Dead Stop")
In 2268, upon departing from Sigma Iotia II, Doctor McCoy related that he had accidentally left his communicator behind on the planet. Captain Kirk and Spock realized that the highly-imitative Iotians would take the communicator apart, learn how the transtator worked, and possibly begin to emulate the technology of the Federation. (TOS: "A Piece of the Action")
Transtators also formed part of a starship's power system. Miles O'Brien accidentally disconnected a transtator from the power grid of the USS Enterprise while infiltrating that vessel in 2268, causing a localized power blackout. (DS9: "Trials and Tribble-ations")
Despite advances in computer technology, such as isolinear chips and bio-neural gel packs, the transtator continued to be used into the 24th century. The USS Voyager carried transtator assemblies aboard, diagnostics of which were routinely performed by operations officer Harry Kim. (VOY: "Time and Again")
After the USS Discovery crash landed on The Colony in 3189 and began making repairs, Lieutenant jg R.A. Bryce tracked down a damaged transtator as being part of the problem. He reported to Commander Saru it would need to be completely rebuilt to restore communications, though worried Discovery may not have enough rubindium to do so. Fortunately, a nearby settlement was able to recreate the damaged part using programmable matter. (DIS: "Far From Home")