The New York Times Co. reported today that its second-quarter earnings rose 16.8 percent to $11.03 million (92 cents a share) on revenues of $187.8 million.

The Times said that results surpass the previous second-quarter record of 1979 when the communication conglomerate earned $9.44 million (80 cents) on revenues of $165.8 million. The company's principal holding is the New York Times newspaper.

Times Chairman Arthur O. Sulzberger said that although earnings held up well during the early months of the economic slowdown, "The continuation or deepening of the recession could affect earnings for the remainder of the year."

He noted that earnings were reduced by $1.2 million, about 6 cents a share, because the paper had to pay premium prices for newsprint. Newsprint has been in short supply in recent months, and Sulzberger said the paper expects to lay out an additional $2.8 million "premium expense" for it during the second half of the year.

The times' problems have been worsened by a month-long strike at one of the Canadian mills in which it owns part interest. The strike was settled tentatively last weekend, but will have an adverse impact on third-quarter earnings, Sulzberger said.

In a related development, the Ochs Trust said it plans to sell 700,000 shares of its class A stock in the Times company next month. The family trust, set up under the will of former Times publishers Adolph S. Ochs, will reduce its holdings of class a stock to about 3.16 million shares, or 28.3 percent of the total. The trust now controls 34.6 percent of class A stock, which elects 30 percent of the board of directors and has limited voting rights.

The company said that the New York Times newspaper had an operating profit of $9.9 million in the second quarter compared with $8.4 million in the second quarter of 1979.

The newspaper recorded a 10 percent gain in advertising linage during the first half of the year.