[Paul Ross]

Uh, there would not have been a network back then. The phone would be dead.

[jimbo123]

They worked everywhere on Star Trek...

[Malsua]

Uh, there would not have been a network back then. The phone would be dead.

No one time travels alone, except Titor. It could be a circa 2525 era walkie talkie and this person is yakking with their friend about being on the set of a Charlie Chaplin film.

[library user]

Uh, there would not have been a network back then. The phone would be dead.

From the comments:

Everyone's saying it COULD be a time traveler on a cell phone. But that it would be impossible because there's no cell phone towers. Uhh...what? lol I mean, if he's an actual time traveler, that would mean he's from the future. So who's to say there HAS to be cell phone towers in order for cell phones to work in the future?