Navy Secretary John F. Lehman Jr., in disciplining General Dynamics Corp. yesterday for giving former admiral Hyman G. Rickover illegal gratuities, referred to the findings of a special gratuities board established last November.

The board investigated charges that General Dynamics gave Rickover's wife a pair of earrings valued at $1,125 while the admiral supervised submarine construction at the company's Electric Boat division.

Lehman said most of the gratuities were "encouraged or even demanded" by Rickover and said his were "clearly out of line and unethical, if not illegal."

Lehman added that the board found no evidence that Rickover proffered any favorable treatment and said he was "always rigorous in negotiations with General Dynamics and very tough."

Rickover, 85, who retired from the Navy in 1982, also received gratuities from three other contractors -- Newport News Shipbuilding & Dry Dock Co., General Electric Co. and Westinghouse Electric Corp. -- but the amounts and types of gifts are still under investigation, according to Lehman.

In an interview last July, Rickover said that he accepted gifts from Electric Boat and other shipbuilders when the companies launched ships and he considered the practice proper.

He said he did not report the gifts and did not know their value, although he acknowledged that "over a period of years, it could add up to something."