What was going on when I was born?

An article in Business Day on May 21 about the day's stock trading incorrectly described the ownership of a videotex system known as Telidon. It is a Canadian operation not associated with Teledyne Industries.

The Federal Trade Commission decided yesterday not to block the $1.8 billion takeover of the Kennecott Corporation by the Standard Oil Company (Ohio). In doing so, sources close to the Government agency said, the four-member panel rejected, by a 3-to-1 vote, a staff recommendation to sue Sohio on antitrust grounds. Sohio, applauding the decision, said it would close the deal tomorrow, buying Kennecott's shares from stockholders for $62 each. Responding to the favorable news, Kennecott shares rose 1 5/8 points, to 61 1/2, on a volume of more than a million shares. It was the most actively traded issue on the New York Stock Exchange.

''It's taken nearly 25 years to right one of history's great wrongs, and we're not going to stop until we have our Dodgers back. What's Romeo without Juliet? What's Niagara without the Falls? What's Hershey without chocolate? What's Brooklyn without the Dodgers?'' - State Senator Thomas J. Bartosiewicz, Democrat of Greenpoint. (B1:3.)

In a challenge to the Reagan Administration, Democrats on the House Ways and Means Committee began drawing up a new two-year tax relief bill today that the committee's chairman, Dan Rostenkowski, said he hoped ''all Democrats'' would support on the House floor. This statement by Mr. Rostenkowski, at the end of a two-hour, closed-door caucus of Ways and Means Democrats, indicated that the Democrats were preparing for a test of strength with the Administration on the House floor over the tax cuts. One Democratic member of the committee reported that there was an informal committee agreement on a first-year cut of 5 percent and a further 10 percent reduction in 1982. Reagan Backs Three-Year Bill President Reagan has insisted on a three-year bill with 10 percent annual cuts, although he said yesterday that he would accept a 5 percent cut in the first year.

New orders for the nation's manufactured goods fell eighth-tenths of 1 percent in April to a seasonally adjusted $163.3 billion, the steepest decline since last May, the Commerce Department reported today. The report said manufacturers' shipments also declined slightly in April, raising factory inventories and providing new evidence that the national economy is slowing. ''It's a picture of continuing softness,'' said Ago Ambre, a Commerce Department analyst. ''It's a fairly sizeable downturn. It's in line with expectations that the second quarter is a slower quarter than the first.''

Amid Britain's economic gloom stands one shining success story for which Prime Minister Margaret Thatcher has received credit. British Aerospace Ltd., reborn as a publicly traded company, has become a symbol of the free enterprise spirit the Government hopes to encourage in Britain. Denationalized in February, when the Government sold half of the company to the public, British Aerospace recently introduced its first all-new passenger plane in 20 years. The BAe 146, a 70- to 100-seat jet aircraft, is aimed at the fast-growing commuter airline industry.

In a ruling that could benefit thousands of New York City tenants, the Appellate Division of State Supreme Court has ruled that a landlord may not refuse a tenant permission to sublet an apartment without giving a reason. If he does not give a reason, the court said, the landlord has, in effect, consented to the sublet. The unanimous decision by the five-judge panel in the case of Conrad v. Third Sutton Realty Company was hailed as a major victory for lease-holding tenants by lawyers involved in sublet cases.

The story is an American epic: Millions of working people, unable to make ends meet in their native Southland, moving northward in wave after migrating wave, seeking a living in the factories and mills of the Middle West. Dick Jones joined that migration in 1947, before he entered school, when his parents left Arkansas for work building automobiles in Michigan. He grew up to be a millwright, a fixer of big machinery, and he did it well enough to achieve a way of life only dreamed of by earlier generations of blue-collar workers. Last year the dream soured and the jobs dried up as the automobile industry retrenched. Now Dick Jones has joined another migration, this one in the opposite direction, to Houston, a city with a surging economy that has lately made it the workingman's mecca that Detroit once was.

LAST week, another in a seemingly endless stream of fad diets hit the best-seller list. If as many Americans as bought these miraclepromising books actually lost a significant amount of weight and kept it off, the market for future fads would soon disappear. In fact, however, the main reason there are so many best-selling fad diets is that none of them work in the long run for the vast majority of people who try them. The obesity specialist Dr. Theodore van Itallie of St. Luke's Medical Center says that about 90 percent of dieters fail to keep off their lost pounds. Each new diet offering actually creates the demand for its successor. Millions may try a popular diet, even stick to it faithfully for a few weeks or months and lose some weight. But sooner or later they tire of following someone else's formula, go off the diet, return to their old eating habits and regain the weight - and usually then some. When the next fad diet comes along, they're ready to try yet another magical ride on the weight-loss seesaw.

BERKELEY,Calif. WHERE American gastronomy is concerned, there is one commodity that is rarer than locally grown black truffles or homemade foie gras. That is a chef of international repute who was born in the United States. Even rarer is such a celebrated chef who is a woman. There is, however, one here in Berkeley who could justifiably deserve such renown. Her name may not be a household word from Maine to California, but many culinary experts, both here and abroad, sing her praises without reservation. Alice Waters is chef-proprietor of Chez Panisse, a cunningly designed, somewhat raffish establishment with a noteworthy menu and kitchen. One of the most euphoric and enthusiastic appraisals of her work came from Christian Millau who, along with his colleague, Henri Gault, publishes a guide to restaurants in Paris. Writing in his monthly guide, Mr. Millau stated that dinner at Chez Panisse had been his most memorable experience in the San Francisco area.

The Reagan Administration is ''on the brink'' of approving the sale of advanced fighter planes to Venezuela, a step that would reverse longstanding American policy against the introduction of advanced arms into Latin America, Government officials said today. The decision to sell a limited number of F-16 jet fighters, among the nation's most advanced warplanes, has been endorsed by senior officials at both the State and Defense Departments. President Reagan is expected to give his approval within a matter of days, officials said. Plane Was Tested by Venezuelans The Venezuelan Air Force has already test-flown the F-16's, according to Defense Department officials, and has asked to purchase 16 to 24 of them.

An article yesterday about a United Nations conference on the Vietnamese presence in Cambodia incorrectly identifed the Cambodian faction that Secretary General Kurt Waldheim refused to invite. China and the Association of South East Asian Nations had asked for an invitation to representatives of former Prime Minister Pol Pot.