In 1986, General Signal acquired Drytek, Inc., a plasma dry-etch company founded in August 1980 by Walter W. Zafiropoulo. From that time he served as Drytek's President and CEO under General Signal as well.
In July 1987 Zafiropoulo also became President of Kayex, a semiconductor equipment manufacturer unit of General Signal.
In February 1989, Zafiropoulo was promoted to become President of General Signal's subsidiary Semiconductor Equipment Group International, yet another semiconductor equipment company. He held the dual position of President of both that company and of Kayex at that time.
In September 1990, Zafiropoulo was promoted to President of General Signal's Ultratech Stepper Division.
In March 1993 Zafiropoulo acquired certain assets and liabilities of the Ultratech Stepper Division of General Signal, and the new company became independent, as Ultratech Stepper, Inc. Zafiropoulo became the President, CEO and Chairman of the newly independent Ultratech Stepper. Later it was renamed Ultratech, Inc.
In 1993 General Signal sold off Drytek, Inc. to Lam Research Corporation.
General Signal became further streamlined in the mid 1990s through the divestment of Leeds & Northrup, which had formerly been part of the process controls sector. It also divested Dynapower/Stratopower, which had formerly been a part of the industrial technology sector.
In 1997 General Signal reported US$1.95 billion in sales. Electrical controls accounted for nearly half of 1997 revenues, with process controls making up a third, and industrial technology, less than a fifth.
General Signal was located at 1 High Ridge Park in Stamford, Connecticut. By 1997 the company had a presence on the internet at http://www.generalsignal.com/ which now redirects to the SPX website.
By August 1998, with 1997 sales of just under US$1 billion, SPX moved to acquire General Signal Corp., a company twice its size, for US$45 per share in stock and cash, in a US$2 billion deal. With the acquisition SPX sought to enter the electrical and industrial controls business.
The deal was completed in the fourth quarter of 1998. General Signal shareholders ended up with 60% ownership of the combined entity, which retained the SPX Corporation name and headquarters. Michael Lockhart, General Signal's President and CEO, left upon completion of the acquisition, along with General Signal's other senior officers.
SPX expected to receive cost savings of US$55 million to US$60 million by 1999 in the first full year after the merger.