Comment Not a mobile phone... (Score 1) 685
When time travel eventually becomes possible, I'm quite sure we'll have progressed past hand-held mobile communicators of this sort (like we did a long time ago, and only use them now for convenience really), and any savvy time traveller would know not to use one in public anyway.
So what has obviously happened here is that at some point in the future, there's some kind of Y2K type disaster waiting to happen and the only way they can avert it is to use a specific kind of technology only used in the original 1924 Siemens carbon amplifier. So the time traveller went back to 1928 (a few years after release so she could be sure there'd be sufficient availability), and wanted to test it to make sure it was working before bringing it back to the future. And that's when she was caught on film! In your face, time traveller!!