Found An Interesting Grouping!

[John Sabato]

it could be that this was a reunion of Soldaten, some years later, who had served at the time mentioned on the sign... instead of it being the date of the photograph. That would allow for voice radio that appears in the photo.

[NoncomRetired]

Originally Posted by John Sabato

it could be that this was a reunion of Soldaten, some years later, who had served at the time mentioned on the sign... instead of it being the date of the photograph. That would allow for voice radio that appears in the photo.

John, I had thought the same by looking at their uniforms, they look more Wiemar than Imperial, but from 1907 to Weimer Republic is a long time, especially during four years of trench warfare and that being seven years after they served together in 1907. The photo raises all kinds of questions I'd be interested in knowing the answers to.

[Norme]

I don't think it's a portable radio, early radios were massive affairs. The picture looks like a staged studio shot and the furniture and accessories are props. The mysterious device might well be a full-plate camera body with the lens removed.
Regards, Norm

[sheepherder]

Originally Posted by Norme

I don't think it's a portable radio...The mysterious device might well be a full-plate camera body with the lens removed.

...Or a signal lamp...

http://www.ebay.com/itm/ANTIQUE-WWII...-/230988515518

German WWII signal flashlight
This was general purpose model that proved very reliable and was used by the Wehrmacht during the war.

This one is labeled as WW II, but the appearance is similar...

Perhaps a signals battalion???