At the beginning of the story, the author describes a setting which is bleak, dark, derelict and war-torn. This immediately creates a sombre tone, and perhaps a foreboding mood.

The very first image in the story is of "The red sunset, with narrow, black cloud strips like threats across it." A sunset in literature often foreshadows a figurative as well as a literal darkness to come. The "red" in this instance also perhaps connotes blood. The "black cloud strips" also foreshadow this aforementioned darkness. Dark clouds in a more literal sense foreshadow rain or perhaps a storm. The simile comparing these clouds to "threats" also adds an impression of menace to the scene. When the weather reflects the mood in this way, or foreshadows what's to come, this is a technique called pathetic fallacy.

Subsequently, the impression of darkness in the opening line is compounded by images such as "the mute darkness," "the veil of the dusk," "the darkling earth," and "the darker shadows of young trees." The darkness is also accompanied by an eerie silence, signaled by the adjective "mute." The overall impression, or mood, is of the eerie calm that sometimes precedes a storm. The darkness and the silence also add to the impression of an inhospitable setting, as does the reference to "the greater cold of night."

There are also clear signs that this setting has been ravaged by war. The frozen mud is imprinted with "the toothed impress of great tanks" and there are all around "the scars of gigantic bombs" as well as "tangled and multiple barbed wire." The reference to scars is an example of personification. The land is personified as an injured victim of war, as if to help us, the readers, empathize with the setting on a personal, emotional level. There is another example of personification when the author describes the road which "crept" through the "isolated weed stalks of the prairie." The word "crept" contributes to the impression of the land as an injured victim of war, creeping and crawling away from the devastation.

The setting in "The Portable Phonograph" is bleak and barren.  It is a setting of devastation. 

The landscape in the story has been devastated by conventional warfare.  Reading it today we might think of nuclear aftermath, but the story was actually written before nuclear weapons were invented, if only by a few years.

Everything is desolated.  The humans in the story are basically starting from scratch, with the exception of a few elements of their previous lives, such as the phonograph.  Whatever has survived, of course, carries much importance for the men:  items such as the phonograph, which serves as a link to the past and a link to the beauty that once was.