Comtech Telecommunications Corp. Monday posted declines in net sales and net income for the fourth quarter as higher sales of microwave amplifiers failed to offset declines in telecommunications transmission and mobile data communications. The Melville company reported a 31.5 percent decline in net income to $5.5 million for the quarter ended July 31, on a 13.3 percent decrease in net sales... Comtech Telecommunications Corp. Monday posted declines in net sales and net income for the fourth quarter as higher sales of microwave amplifiers failed to offset declines in telecommunications transmission and mobile data communications.