WASHINGTON (AP) _ The only thing missing from Lt. Col. Oliver North's much-discussed slide show on Nicaragua was the slides.

North on Tuesday gave a scaled-down version of his pitch for U.S. aid to the Nicaraguan rebels after Iran-Contra panel members argued over whether to provide him with a free national television audience for his well-practiced appeal.

The question of whether North would repeat the slide show for the committee - and if so, under what circumstances - dominated the first two hours of Tuesday's hearing. North had given the presentation scores of times for potential donors to the Contra cause and supporters of the Reagan administration's Central American policies.

Sen. Warren Rudman, R-N.H., vice-chairman of the Senate committee, had said earlier in the week the North slide-show briefing on Nicaragua was the first strike of a ''one-two punch'' strategy used to solicit donations.

North made the case for the Contras by saying the United State must counter a Soviet threat, the senator said, and then the Marine officer left the room without actually soliciting money while a second punch was delivered by professional fund-raisers.

Since Congress had barred administration officials from soliciting such contributions, conservative committee members said, the only fair thing to do was to have North reconstruct his presentation for a national audience.

''We feel very , very strongly that it's only fair the Colonel North be permitted to provide this presentation,'' said Rep. Richard Cheney, R-Wyo., vice chairman of the House panel.

But others protested that this would amount to handing North a national platform to promote the Contras, whose funding comes up for congressional renewal later this year.

Sen. Daniel K. Inouye, D-Hawaii, the committee's chairman, said that for security reasons, the blazing television lights inside the Senate Caucus Room could not be lowered to permit the slides to be seen.

He offered a nighttime slide showing in another room.

Several conservatives objected, saying that would pit North's performance against the All-Star baseball game or the television quiz show ''Jeopardy.''

Finally, a compromise was reached: the slides were to be put into the printed hearing record and North would get his say - in part.

North, selecting from a carousel holding 57 slides, did not actually show any of them. But he was permitted to describe them, saying one showed Soviet warships steaming ''16 miles off ther coast of Louisiana.'' Others, he said, showed Soviet submarines, a Soviet port and aerial facilities in Nicaragua, and Cuban troops in Africa serving as ''a mercenary Soviet army.''

There were photographs of Nicaraguan President Daniel Ortega and a quotation asserting that Nicaragua's leaders sought ''a Marxist-Leninst'' future for their land.

Finally, North said, there were photographs of the Contra insurgents, photographs he said showed their uphill struggle against the Sandnistas with inadequate weaponry and supplies.

The 57th slide, North said, ''is a photo showing the grave of one of the freedom fighters.''

North said his last words as that slide appeared on the screen had been, ''We've got to offer them (the Contras) something more than a chance to die for their own country and the freedoms we all believe in.''

Without photos, North's presentation lacked some of the impact which previous witnesses have ascribed to it. There was, for instance, no laughter at an apparent joke - when North referred to one slide showing ''agricultural rocket launchers'' because, he said, some Soviet military aid to Nicaragua came in crates marked as agricultural supplies.

North also appeared to tone down some remarks he made in other versions. To the committees, he mentioned an airfield in Nicaragua large enough to accommodate Soviet Backfire bombers. An earlier witness to the North presentation had told the committees that North referred to the ability to land Backfire bombers there after a nuclear attack on the United States.