(((Hugs))) No news is good news - just keep reminding yourself of that. If something goes wrong, then they call. If everything is going smoothly - getting a call isn't guaranteed...it might happen or it might not.
Did you get the box and the form letter? They are probably keeping him much too busy and much too tired to be home-sick.
Hint: activate the card so he doesn't waste time on that.
At Boot Camp there is no free will. If they are told they get a phone call, they make a phone call. However, it is hit and miss. My son called the first day and after Battlestations.
As someone else mentioned, no news is good news.