President John F. Kennedy secretly recorded about 600 of his White House meetings and telephone conversations during the last 16 months of his presidency--apparently without the knowledge of other participants.

It has been known for several years that Kennedy recorded some meetings and phone conversations from his White House days but the extent of the recordings, the names of the participants and the subject matters have never been disclosed.

A 29-page log obtained by The Washington Post from the Kennedy Library in Boston shows the recordings were made from July, 1962, until November, 1963, the month Kennedy was assassinated. The tapes contain a vast amount of unreleased information, including many highly classified meetings of the National Security Council on such subjects as the Cuban missile crisis, Berlin and Vietnam, and high-level discussions of domestic controversies such as the 1962 integration of the University of Mississippi.

There are recordings of 325 meetings in the Oval Office or the Cabinet room and another 275 personal telephone conversations Kennedy had with family members, his Cabinet, White House staff, former presidents, legislators, world leaders and diplomats.

The disclosure of a secret Oval Office taping system maintained by President Richard M. Nixon became a sensational element in the Watergate scandal. Those tapes eventually provided evidence for the impeachment proceedings that led to Nixon's resignation in 1974. At least two other presidents, Lyndon B. Johnson and Franklin D. Roosevelt, also taped private conversations in the White House, but the full scope of JFK's taping system has not been widely known.

"It is bound to become the primary source on how John F. Kennedy's mind worked," said Dan H. Fenn Jr., director of the Kennedy Library in Boston where the recordings and preliminary transcripts, made by archivists over the last several years, are kept. The Washington Post has over the last several years requested access to the tapes but it has been denied because of classification and privacy considerations. Fenn said that some of the tapes and transcripts of the recordings, donated to the library by the Kennedy family in 1976, will be made available in the near future. Burke Marshall, a former assistant attorney general in the Kennedy administration and head of a three-member committee that controls release of material from the Kennedy Library, said last night: "Our position is going to be that we should open this material in an orderly fashion."

He said he could not set a time frame for this process, but added that transcripts are being made and that many will have to undergo a declassification review by the National Security Council.

Evelyn Lincoln, Kennedy's personal White House secretary, and several Secret Service agents who installed and maintained the system of recordings were the only ones who knew the full details of the secret recording system, according to well-informed officials.

"I was the engineer," Lincoln said in a recent interview. Lincoln said Kennedy had a switch in his office that activated a red light at her desk. That was the signal, she said, to begin the recording system. According to Lincoln, if the red light went on when Kennedy was on the phone, she was to record the conversation on the dictabelt system hooked into his phone. If the light went on when he was in the Oval office or the Cabinet room, she was to start the regular taping system for those rooms. The log from the Kennedy Library indicates there may also have been some recordings made in a study in the president's residence. But one person knowledgeable about the taping system said he believed there was such a system but no actual recordings were made of Kennedy's conversations there.

"He was very conscious of history," Lincoln said. "He was always wanting to get exactly what was said. . . to pinpoint precisely what was said. These were for history and he wanted to have them for that and he never once went back and listened to one."

Theodore C. Sorensen, special counsel to Kennedy and probably his closest aide, was shown a copy of the log last month. "I'm dumbfounded," Sorensen said, adding that he had no idea whatsoever that such recordings were being made.

The log listing each recording reads like a Who's Who of the early 1960s. It includes recordings made between Kennedy and the following: his wife Jacqueline Kennedy; his brothers Robert F. Kennedy and Edward M. Kennedy; former presidents Dwight D. Eisenhower and Harry S. Truman; his vice president, Johnson; Sens. Barry Goldwater, Hubert H. Humphrey, Henry M. Jackson and J. William Fulbright; Senate Majority Leader Mike Mansfield, House Speaker John W. McCormack, Secretary of State Dean Rusk, Secretary of Defense Robert S. McNamara, national security adviser McGeorge Bundy, CIA Director John A. McCone; various military leaders, including Chairman of the Joint Chiefs of Staff Maxwell Taylor and Gen. Douglas MacArthur.

Robert Kennedy, Secretary of State Rusk and Defense Secretary McNamara appear on the recordings most often, each about a dozen times, according to the log.

The log does not list each participant in the 325 meetings but does give the key person attending or the subject matter of discussion. Given the subject matters, which cover the broadest range of foreign and domestic policy, it is doubtful that many Kennedy intimates or major political figures of the time escaped his recordings.

The log also substantiates Lincoln's statement that the recordings were made with an eye toward history. Nearly every major issue of the Kennedy presidency--tax bills, the nuclear test ban treaty, the economy, foreign visits, civil rights, defense policy, foreign aid--are mentioned in the log as topics of discussion in various meetings.

Also recorded, almost certainly without knowing their words would be saved for history, were labor leaders George Meany and Walter Reuther, Chicago Mayor Richard J. Daley, New York Mayor Robert Wagner, Saturday Review editor Norman Cousins, California Gov. Edmund G. (Pat) Brown Sr., Texas Gov. John B. Connally, pollster Lou Harris, White House staff member and historian Arthur Schlesinger Jr., Kennedy's brother-in-law and Peace Corps director R. Sargent Shriver.

Henry A. Kissinger, who appears many times on the Nixon taping system in the early 1970s, is listed on an April 26, 1963, tape when he was a special foreign affairs adviser to Kennedy.

Archibald Cox, who later as Watergate special prosecutor initiated the subpoena of Nixon's tapes, was secretly recorded by President Kennedy in two personal conversations, both while Cox was the solicitor general for the Kennedy administration. One Kennedy-Cox call was in September 1962 about the crisis of admitting James H. Meredith, a black, to integrate the University of Mississippi. The second was on Aug. 22, 1963, according to the log, and concerned the Tidelands oil issue involving Louisiana.

The taping system was installed in great secrecy by the Secret Service in the summer of 1962 and was removed Nov. 22, 1963, the day Kennedy was assassinated, according to an official familiar with the system.

Overall the Kennedy Library has 125 reels of tape from Oval Office or Cabinet meetings, totaling 325 conversations. The first was recorded on July 30, 1962, and the last on Nov. 7, 1963. More than three dozen NSC meetings were recorded including many, if not most, of those involving the October 1962 Cuban missile crisis.

In addition, the log shows the 275 phone conversations were recorded over a 14-month period on 27 dictabelts, the first on Sept. 10, 1962, and the last on Oct. 29, 1963.

While the contents of the recorded conversations are unknown, the range of topics listed in the logs is broad. Subjects include Kennedy discussions with: Mississippi Gov. Ross Barnett on the Meredith crisis; longtime friend LeMoyne Billings on a "missed plane connection"; California Gov. Brown on the "defeat of Richard Nixon in California gubernatorial election"; Connally for "congratulations on election" and "John McCone's testimony on the missile crisis."

Like presidents who came after him, Kennedy discussed the "use of polygraphs in tracing defense leaks" with his defense secretary, according to one log entry, and he appeared concerned about "keeping the CIA out of the Peace Corps," according to another.

One telephone log reports a conversation with a person identified only as Al on the subject of a "movie version of PT-109."

The president recorded a conversation with one official about the location of an Internal Revenue Service facility, and another with Rusk on the illness of Pope John XXIII.

Several conversations with Edward Kennedy, a newly elected senator, were recorded. The topics included "meeting with wool industry representatives re international trade," "EMK's speed-reading course" and "prospective visit/speech by JFK to Boston College on 4/19/63."

The president recorded his conversation in March, 1963, with then Treasury Secretary Douglas Dillon on "IRS rules on expense accounts" and another conversation that month with an aide to Robert Kennedy on the subject of a "U.S. hockey team loss."

The identities of six of the people Kennedy talked with and had recorded are blocked out on the log obtained by The Washington Post. One is known to be Jacqueline Kennedy. The subject matter of these six conversations is also deleted on the log.

Since the Kennedy taping system was not automatically started by a voice speaking, such as the voice-activated system used by Nixon, there are probably only about 300 hours of conversation. By contrast, the Nixon taping system recorded about 4,000 hours of meetings and telephone conversations.

Both Evelyn Lincoln and officials at the Kennedy Library where the tapes are stored said that it was President Kennedy who personally decided what to have recorded. In about a dozen cases it is clear that the switch activating the taping system was accidently turned on because the log shows that Kennedy's secretary was simply asking for a White House operator to make a routine call.

When the existence of the Nixon tapes was first revealed during the Senate Watergate hearings in July 1973, there were widespread expressions of shock and outrage from rival political figures, including some who served under President Kennedy who did not know of the existence of the secret recording system their own president had maintained.

David Powers, former appointments secretary to the late president and curator of the JFK Library in 1973, said at the time he knew of no similar telephone monitoring system in the Kennedy White House.

"I cannot recall this ever being done," Powers was quoted at the time. "If it had been done, I would have known it. I was in the president's office every day."

Historian Schlesinger reacted similarly. A secret taping system would have been "inconceivable," he said, because Kennedy would never have approved such an "incredible" system.

According to library director Fenn, he informed Kennedy aides after their public remarks that there were also Kennedy tapes. Fenn then issued a statement which provided a brief account of the existence of Kennedy tapes, including the fact that some were to be transcribed by a secretary working for the family. The recordings were said to be still in the hands of the Kennedy family, not yet turned over to the library. No further exploration followed and it remained unknown that Kennedy's secret tapes covered some of the most sensitive meetings of his presidency.

A spokesman for the LBJ Library in Austin, Tex., said this week that there is an extensive collection of Johnson tape recordings given to the archives by a former personal secretary under a deed that requires they be kept sealed for 50 years. The papers and other materials that reside in the presidential libraries have usually been treated as private property by the former presidents and their heirs, who usually donate the material to the National Archives under restrictive deeds that define the public access to the documents.

In a similar deed, the Kennedy family donated JFK's papers, including these tape recordings, to the National Archives for the Kennedy Library in 1965 but the tapes were not actually delivered to the library until 1976. A review committee was established to determine when the public may have access to the various materials.

An explanation issued by the Kennedy Library said:

"The recordings must first be fully and accurately transcribed, and then reviewed to determine which portions may be opened to research under the restrictions, terms and conditions of the Feb. 25, 1965, deed.

"A further complicating factor is that many of the tapes are recordings of high-level national security meetings, and contain national security classified information. In addition to being reviewed against the Kennedy deed, these items must be reviewed by proper authorities in Washington to determine when they can be released for public research."

More recently, a historian uncovered a small collection of recordings of private conversations and meetings made in the Oval Office by President Franklin D. Roosevelt. The recordings reveal no great secrets about the FDR presidency but do portray the expansive character of Roosevelt and his ebullient monologues.