While the infamous White House taping system was being planned, President Nixon suggested that he have a button to turn it on and off manually, but was dissuaded by an aide who says he thought the president was too clumsy. Therefore, a voice-activated system was installed and Nixon quickly lost awareness that his every conversation was being recorded, says former White House chief of staff H.R. Haldeman in an article for the National Archives publication ``Prologue.'' The tapes led to Nixon's resignation in August 1974 when they provided damning evidence that he had consented to the White House cover-up of the Watergate break-in. Haldeman said Nixon had resisted the idea of taping conversations but reluctantly agreed it was the best way to get an accurate record of meetings. ``He suggested we might install the same kind of switch- or button-operated machine that (Lyndon) Johnson had used.'' Haldeman wrote. ``That would allow him to turn the system on or off as he thought best.'' The former aide continued: ``I responded, `Mr. President, you'll never remember to turn it on except when you don't want it, and when you do want it you're always going to be shouting _ afterwards, when it's too late _ that no one turned it on.' ``I added, silently, in my own thoughts, that this president was far too inept with machinery ever to make a success of a switch system.'' The taping system that finally was installed was activated by the Secret Service's locator system which keeps track of the president's whereabouts. Eventually, five microphones were put in the president's desk, two were in wall lamps at each side of the fireplace on the opposite side of the Oval Office, and there were others in the Cabinet Room, Nixon's office in the Old Executive Office Building and at Camp David, Md., the presidential retreat. ``The historiography of the Nixon administration will eventually be much the richer as a result of Richard Nixon's decision to tape-record his meetings and telephone conversations,'' Haldeman writes. ``Nixon was not thinking of historians when he made this decision, but they will be the ultimate beneficiaries.'' Haldeman's account is much softer in tone and less critical of Nixon than when he described the same events in a 1978 book, ``The Ends of Power,'' which he said ``was unfortunately sensational in many instances where I would have preferred it to be more reasoned and thorough.'' In the book, Haldeman said Nixon had ``fudged'' the tape story in various ways, ``climaxing with the assertion on television in 1977 that he had ordered me to destroy all of the tapes.'' There is no reference to that in the Prologue article. Haldeman says he is amazed how quickly he forgot about the system once it was in place. ``For a short time, I worried that it might not be working, and I dispatched someone to test the machinery,'' he writes. ``But the worry quickly passed, as did any awareness at all that Nixon's conversations _ my conversations, often _ were being taped. I think Nixon lost his awareness of the system even more quickly than I did.'' Nixon himself has written that ``initially I was conscious of the taping, but before long I accepted it as part of the surroundings.'' Nixon fired Haldeman in April 1973 at the height of the cover-up of the June 1972 break-in, when burglars placed bugs in telephones and searched files in Democratic Party headquarters in the Watergate Office Building. Haldeman served an 18-month prison term for his part in the affair. Haldeman said he chose to write about the taping system because the National Archives plans to release 60 hours of the recordings next year for public listening.