Sen. Barry Goldwater called on former President Nixon yesterday to make a special television appearance and "honestly explain why Watergate happened.

Goldwater, the conservative Republican from Arizona, said Nixon should go beyond the explanations he offered during an hour and a half interview with David Frost last week and say, "This is what happened. This is how the breakin came about."

After the first Frost interview, Goldeater said no Republican "in his right mind" would ever consider Nixon as a political candidate for any office.

"Now I have to admit that for is a very harsh judgment on a man who was a friend for many years," Goldwater said yesterday.

The senator said he often campaigned for Nixon's election and Nixon campaigned "for me whole-heartedly . . . at least in his conception of the term."

Nonetheless, Goldwater said until Nixon makes a full explanation of the origins of the scandal which drove the former President from office, the Republican Party should block any return by Nixon to public life.

"When he does that," Goldwater said in a statement. "I will be willing to reappraise my feeling towards him, but not until then.

"His actions have destroyed the political party to which I devoted my life."

In the Frost interview, Nixon admitted to "letting the American people down" and lying during attempts to shield his closest aides during the investigations into the origins of the original break-in at Democratic National committee headquarters June 17, 1972.

But there was little discussion during the interview of the break-in itself or who ordered it.

Goldwater said only if Nixon appears on television to tell the truth and admit the "tragic mistake" of Watergate "will the American people forget the trauma, disaster, and the horror of the Watergate scandal."