Thirty-seven Explorer Scouts have already signed for the win ter camp at McCall Dec. 28 to 31,Scout Executive Stewart Norton announced today. The youths will camp in the snow three days, learning winter camping survival — techniques from instructors from the Air Force Survival School at Mc Call. The camp is limited to 60 boys. Norton said registration will probably close tomorrow. Nampans who have signed up are Harvey Powell, Willard Long, James Burkey, Larry Rob ertson, George Covert, Fred Deal, Edward Weide and Fred Norton.