Ronald Bornstein, a former vice president of the Corporation for Public Broadcasting, has been named by the board of National Public Radio to direct the day-to-day management operations of the network, now strapped by a $5.8 million deficit.

Bornstein, acting chancellor of the University of Wisconsin-Extension, will take over many of the management responsibilities of NPR president Frank Mankiewicz. He will have the title of acting chief operating officer and serve on a part-time basis. The interim appointment runs from May 9 to Oct. 1. His selection had been expected since Mankiewicz announced he was stepping down.

"Ron is someone who has played this role before at CPB, also on a temporary basis," said Myron Jones, president of the 17-member NPR board. "He is well known in public radio, has a great deal of experience, is known for being a very good manager, and is known as a fiscal conservative. We--the management and the board--got into these problems because we were economically optimistic."

Mankiewicz, president of NPR since 1977, announced Tuesday that he will leave NPR shortly. In the interim, Mankiewicz will continue his liaison work with Capitol Hill, federal agencies and other funding sources.

At the annual National Public Radio conference in Minneapolis this week, the network's deficit was reassessed from $2.8 million to $5.8 million.

At that meeting, the member stations rejected a board proposal that they pay programming fees. However, the membership voiced support for a number of fund-raising efforts.

The NPR board voted to terminate the news portions of the "NPR Plus" programming. "Not as many people signed up as we anticipated and we can't run it at a loss," said Jones.

The Corporation for Public Broadcasting, which distributes money to public radio and television outlets, has offered some undisclosed help.

"I don't think they meant that they would look around for their checkbook," said Jones. "I don't like the phrase bailout; that's not what we are asking. But we are in a jam."

Further trimming of personnel and programming is expected. Last month NPR fired 37 employes and announced cancellation of some shows.

Bornstein has been at Wisconsin in a variety of leadership positions since 1967, including director of the campus radio and television stations.