Under outspoken pressure from Capitol Hill, the Corporation for Public Broadcasting and National Public Radio resumed negotiations yesterday over a $9.1 million bailout loan for the public radio network.

Separate meetings were set for each side yesterday with Rep. William Natcher (D-Ky.), chairman of the House Appropriations Committee; Rep. John Dingell (D-Mich.), chairman of the House Energy and Commerce Committee; and Rep. Timothy Wirth (D-Colo.), chairman of the Energy and Commerce subcommittee on telecommunications.

Sen. William Proxmire (D-Wis.) met Tuesday with Ronald C. Bornstein, acting chief operating officer of NPR, and sent a letter to Sharon Percy Rockefeller, chairman of the CPB board. Yesterday Proxmire said, "The parties bargaining over the future of NPR owe it to the American taxpayer, who spends $130 million on public broadcasting each year, to keep NPR alive. They should be firmly ushered into a locked room and told to stay there until they come out with an acceptable compromise."

After separate meetings with the NPR and CPB executives, an aide to Wirth described the congressman's sessions as "informational" and added, "Wirth strongly urged that they resolve their narrowing differences and quickly reach an agreement, because it would be a travesty for NPR to go under."

The meetings with congressional members were called to discuss the impasse between the two parties over CPB's insistence that ownership of the network's satellite equipment be transferred to a group of CPB-selected NPR stations. The NPR board of directors rejected that proposal earlier this week. If NPR does not receive the $9.1 million loan or an interim loan by tomorrow, it faces bankruptcy.

Yesterday's talks between CPB and NPR negotiators were described by Edward Pfister, CPB president, as "constructive and meaningful." Progress after five hours was described by one CPB official as "guarded."

The meetings with congressional leaders took on additional urgency because some of the legislators thought the CPB-NPR stalemate was giving all of public broadcasting a bad name. "The man in the street looks at the problems and sees public broadcasting, he doesn't differentiate," said one Capitol Hill aide.

This spring Dingell asked Congress for a 5.6 percent increase in public broadcasting funds. Though approved in committee, the increase is now on the back burner while NPR's financial difficulties are straightened out. Dingell also requested an audit of NPR books by the General Accounting Office and threatened to hold congressional hearings if solutions were not found soon at NPR.

In his letter, Proxmire, who is the ranking Democratic member of the Senate Appropriations subcommittee on labor, health and human services and education, the committee that oversees the public broadcasting budgets, urged Rockefeller and the CPB "to go the extra mile." The letter said, "It is my understanding that those negotiations are currently floundering and that National Public Radio may be forced to close its doors later this week. This would be a tragedy not only for NPR but the corporation in view of the corporation's responsibility for overseeing NPR performance."

Bargaining resumed yesterday morning, said Rockefeller, who announced the development to the NPR member stations at noon. Officials of CPB were scheduled to hold a systemwide discussion with the stations, but it was canceled as negotiations reopened.

The loan proposal broke down Saturday after CPB insisted on transfer of the ownership of NPR's satellite equipment to a CPB-selected trusteeship of NPR member stations. The NPR board rejected the proposal Monday, claiming that CPB was attempting to restructure the network under duress. Both CPB and NPR spent two days disagreeing with one another in public, and at one point Pfister said, "All the hotsy-totsy letter exchange, it has all got to stop."

CPB denied a takeover effort but said it was attaching conditions because of the congressional mandate to oversee the financial business of NPR. However, CPB has so far refused to budge on the proposal, and before the congressional intervention, talks had broken down.