Earl F. Landgrebe, 70, an Indiana Republican who during three terms in the House of Representatives gained a reputation as a colorful loner who advocated his own brand of conservatism, died June 29 at his home in Valparaiso, Ind., after a heart attack.

Mr. Landgrebe, who served in the House from 1969 to 1975, gained national attention in 1974 for his spirited defense of Richard M. Nixon's embattled presidency.

In February 1974, the House of Representatives voted 410 to 4 to direct its Judiciary Committee to start impeachment hearings against Nixon. In August 1974, following the president's resignation, the House voted 412 to 3 to accept the committee's report as part of the House's official record and thank the committee for its "conscientious and capable inquiry."

In both cases, Mr. Landgrebe voted with the minority.

But as a champion of Nixon's cause the congressman was best known, perhaps, for this statement, which he made the day before the presidential resignation:

"Don't confuse me with the facts. I've got a closed mind. I will not vote for impeachment. I'm going to stick with my president even if he and I have to be taken out of this building and shot."

Mr. Landgrebe also was remembered for his lone voice against a cancer research appropriation bill. He later explained that he thought the appropriation was too large and that acheiving a cancer cure would only change "which way you're going to go." He also once voted "no" on a quorum call, though he could not later remember why he had done so.

But he was not against everything. He told the voters of his district in 1974 that he favored detente with Moscow because it allowed him "to get through the lines" to pass out Bibles in the Soviet Union. On one occasion when he visited the Soviet capital as a member of a House delegation he was picked up by authorities after distributing copies of the Bible in the lobby of a Moscow theater, at a Tashkent park and hotel, and at several bookstores.

In the 1974 election campaign, Mr. Landgrebe followed the conservative Republican platform that had long appealed to the voters in his rural northwest Indiana district. The man he had succeeded was Charles Halleck, who represented the state's second district for 34 years and had been the House Republican leader.

Staunchly Republican as the electorate seemed, Mr. Landgrebe had retained his seat by steadily diminishing margins in 1970 and 1972. As the 1974 election approached, New Times magazine named him one of the "10 dumbest" members of Congress. And Indiana's Republican national committeeman told the Wall Street Journal that he would not talk about Mr. Landgrebe, except to note that he "didn't know the Wall Street Journal had a comics page."

On polling day Mr. Landgrebe received 39 percent of the vote and was defeated by Democrat Floyd Fithian, a Purdue University history professor.

After leaving Washington, Mr. Landgrebe worked in the family trucking business in his native Valparaiso. Before his election to the House, he had spent a decade in the Indiana state senate.

Survivors include his wife, Helen; two sons, Ronald and Roger; two brothers, Edward and Elmer, and one sister, Elsie Dye, all of Valparaiso; three grandchildren, and four step-grandchildren.