Sometimes, too much useless knowledge can spoil the fun.
A friend sent me a link to this video last night, because he's either heard of/or been subjected my love of time travel tales via playing in one of my roleplaying game campaigns. (I think he might have been in the game where D&D characters were sent back to ancient Blackmoor.)
When I saw the video, I thought, "Isn't that just a hearing aide?"
Many years ago, I did a little article on hearing aids for I-don't-recall-where-anymore, but during the course of that, I discovered an early development that had been created by Siemens in the 1920s. Back then, I even came across some old print ads that showed an elderly gentleman holding a hearing aid exactly like the woman in the footage is holding whatever she's holding. I spent entirely too long trying to find that ad online, and I discovered that the collective wisdom of the internet has once again sapped the life out of a really cool urban legend (and beaten me to the punch, once again).
While I never did find the ad I remembered, I did find this page at the Siemens website that has a black and white crop from the ad I had been seeking, as well as an image of the hearing aid that woman is using in the clip (I'm fairly certain).
While the cell phone tale is a cool one, it has an additional problem: How would a cell phone operate without cell towers and satellites? And while I'm thinking about it, could a cell phone even connect with the phone networks of the 1920s, with all of the hardwires and operators manually switching plugs from one outlet to another?
Of course, it that WAS a time traveler in the footage, it's possible that she came from a space ship or a TARDIS-like vessel that is itself a "cell tower" or "satellite".... Perhaps all of us non-imaginative nay-sayers have this all wrong!