General Signal Corp. of Stamford, Conn., agreed...

General Signal Corp. of Stamford, Conn., agreed to acquire Andover, Mass.-based GCA Corp., the troubled manufacturer of equipment used to make semiconductors, for between $75 million and $80 million . . . Pasadena-based Beverly Enterprises reported that a class action lawsuit has been filed against Beverly and David Banks, its president, on behalf of purchasers of the company’s securities during the period Feb. 27, 1987 through Jan. 4, 1988 . . . Los Angeles-based National Sanitary Supply Co. announced that it has signed a letter of intent to acquire the Packer-Scott Co. of Oregon for an undisclosed price . . . The World Bank said it approved two loans totaling $565 million for Mexico to boost agricultural productivity and make its fertilizer industry more competitive.