Well, yes, that's one hole in his logic. But it doesn't eliminate some other variety of hand-held transceiver. It's just that the most common example these days is the cell phone -- twenty years ago and someone might have said "communicator" or "walkie-talkie".
Dartz -- while crystal sets could be -- and generally were -- small enough to be hand-held, the "cat's whisker" detector/diode is a rather delicate affair (being, as the name suggests, a hair-thin wire brushing a crystal of galena or other semiconductor mineral) and wouldn't stand up to being toted around. Plus, they didn't have speakers that could be heard over a crowd, even if you held them to your ear like a transistor radio -- they used ear phones because they generated such a weak sound (being powered by the radio waves they picked up, not by an internal power source). If it were a crystal radio, as unlikely as that might be, she'd have a wire from her ear to an object in her hand, pocket or purse instead. (My dad was a Depression-era child and knew how to build one with a cardboard oatmeal canister and box of scraps -- cave optional -- and showed me how to do it when I was a kid; I know from experience that, ruggedness of cardboard aside, they don't hold up to handling too well.)
And it can't be any other kind of period portable radio, because they didn't exist -- powered radio at the time needed vacuum tubes and a wall socket, and tended to be in big boxes. The first man-portable radios were those backpack units you can see in old war movies, where one guy wears the radio while another cranks up the magneto for power before transmitting. And this film predates that technology.
Anyway, the best way to figure this out is to figure out all the other things she could be doing that would look like that, as some of the folks in the comments on that page have. However, some of those suggestions just don't pass the reality check -- anything that involves her shading her eyes would have her holding the whatever-it-is in a different position, as we can clearly see that it's not shading her eyes at all -- the shadows don't line up with the direction of the light. (If anything's shading them, it's the brim of her hat.)
Quite frankly, I personally believe there's a perfectly mundane explanation, mainly because I can't imagine a real time traveler would be so careless as to walk down the street talking on a hand-held radio in 1928. But it's still pretty cool to think about.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.
Dartz -- while crystal sets could be -- and generally were -- small enough to be hand-held, the "cat's whisker" detector/diode is a rather delicate affair (being, as the name suggests, a hair-thin wire brushing a crystal of galena or other semiconductor mineral) and wouldn't stand up to being toted around. Plus, they didn't have speakers that could be heard over a crowd, even if you held them to your ear like a transistor radio -- they used ear phones because they generated such a weak sound (being powered by the radio waves they picked up, not by an internal power source). If it were a crystal radio, as unlikely as that might be, she'd have a wire from her ear to an object in her hand, pocket or purse instead. (My dad was a Depression-era child and knew how to build one with a cardboard oatmeal canister and box of scraps -- cave optional -- and showed me how to do it when I was a kid; I know from experience that, ruggedness of cardboard aside, they don't hold up to handling too well.)
And it can't be any other kind of period portable radio, because they didn't exist -- powered radio at the time needed vacuum tubes and a wall socket, and tended to be in big boxes. The first man-portable radios were those backpack units you can see in old war movies, where one guy wears the radio while another cranks up the magneto for power before transmitting. And this film predates that technology.
Anyway, the best way to figure this out is to figure out all the other things she could be doing that would look like that, as some of the folks in the comments on that page have. However, some of those suggestions just don't pass the reality check -- anything that involves her shading her eyes would have her holding the whatever-it-is in a different position, as we can clearly see that it's not shading her eyes at all -- the shadows don't line up with the direction of the light. (If anything's shading them, it's the brim of her hat.)
Quite frankly, I personally believe there's a perfectly mundane explanation, mainly because I can't imagine a real time traveler would be so careless as to walk down the street talking on a hand-held radio in 1928. But it's still pretty cool to think about.
-- Bob
---------
Then the horns kicked in...
...and my shoes began to squeak.