I’m not sure what this old tube is doing, but it appears on the cover of the September 1929 issue of the Soviet publication Радиолюбитель (Radio Amateur). One would think that the word written on the ground would add some context.  But according to Google translate, “скатертъюборога” means “tablecloth,” so that doesn’t seem to help.

Since I can’t think of any other reason why atheist Soviets would be showing Christian crosses, I assume that these are grave markers.  Modern Soviet tubes have replaced the old models, and this old tube is visiting his fallen comrades at the cemetery.  Perhaps he plans to have a picnic on the tablecloth.