The 4th Signal Company was part of the 4th Infantry Division.The 4th ID landed on D-Day at Omaha Beach, and fought it's way across Europe, ending up in Germany in May 1945.For a brief history of the 4th ID in WW2 see: http://www.grunts.net/army/4thid.htmlhttp://www.grunts.net/army/4thid.html
A signal company was responsible for the set up and maintenance of all communications (field telephones, radio networks, etc.) within the division.
The pictures you have are of Hitler's home near Berchtesgaden, Germany (he actually had two homes in the area, known as the Berghof and the Eagle's Nest).Here's a link to a site with more pictures of the same location: http://www.warfoto.com/berchesg.htmhttp://www.warfoto.com/berchesg.htm
Berchtesgaden became a major "tourist" attraction for US troops during the occupation of Germany.
To find out more info on either just google "4th Ifantry Division" and "Eagle's Nest"