LEAVE IT to those Midwesterners.

While the managers at National Public Radio are shuddering over cutbacks in capital, the producers at Minnesota Public Radio are capitalizing on the popularity of "A Prairie Home Companion."

A live variety show whose satellite broadcast reaches an audience of 2 million listeners across the United States--"Companion's" producer has come out with a catalogue offering products related to the show and other programs carried over the American Public Radio Network.

Named Wireless, Minnesota Public Radio's catalogue features items that range from Aaron Copland recordings to "Mouthsounds," a book on how to sound like a barking dog or dripping water. Borrowing from the Lake Wobegon myth perpetuated by "A Prairie Home Companion" host Garrison Keillor, the catalogue even sells Lake Wobegon T-shirts and Powdermilk Biscuit posters. These items, including note cards with sketches of "The Mary Tyler Moore House" on them, are offered, ironically, "for people who like what they hear on the radio."

Locally, "A Prairie Home Companion" is heard Saturdays at 8 p.m. on WETA-FM (90.9). Though many listeners assume that the show is an NPR production, NPR only coordinates satellite broadcast time of the show. The Corporation for Public Broadcasting owns the satellite, which is part of the Public Radio Satellite System. NPR affiliates that are also members of the American Public Radio Network Minnesota Public Radio and WETA areis have the option of picking up the program.

The eight-page full-color catalogue evolved from the success of "A Prairie Home Companion" and from the creativity of the MPR staff.

An itinerant attraction in 1974, "A Prairie Home Companion" changed theaters before it settled into the World Theatre in St. Paul in March 1978. Today, ticket orders quickly fill the 1,000-seat facility each week.

Sally Pope, Minnesota Public Radio's vice president of community relations, said that to finance such a "weird-duck program" of storytelling and musical performance, its producers had to look farther than the $2,500 that their national underwriter, Cargill Inc., initially gave them. Over the years, Cargill has substantially increased its financial support, and the National Endowment for the Arts has also contributed to the show, Pope added.

When Minnesota Public Radio conducted its pledge drives, it began to solicit not only memberships to the statewide network, but also financial support for "A Prairie Home Companion," which by 1976 was rapidly turning into a cult in St. Paul (national broadcasts began in 1980).

By advertising T-shirts with the Lake Wobegon crest and offering them as premiums for first-time membership, the station gained members while it received money to cover programming costs.

"Today 'A Prairie Home Companion' generates more membership income than any other public radio program," Pope said. With a steady renewal rate, subscriptions to Minnesota Public Radio totaled 50,000 in 1983.

Who designed the T-shirt?

"We're not big on documenting who gets credit for what idea," Pope said. "We don't operate that way; all effort is shared. We're not muscle-bound by bureaucracy."

Anyway, fans didn't care for paperwork; it was all they could tolerate to write to the MPR staff and ask them to sell more products. Like those for the T-shirts, these ads appeared in Minnesota Monthly, MPR's magazine for members.

MPR's Donna Avery hoped Wireless, which appearedin November 1982, would reach "people who enjoy listening to the radio. There are a lot of values that are shared by people who are attracted to public radio," she said. "The audience is very literate."

Although Sally Pope had no exact figures on the catalogue, which was typeset in house, she said, "There is profit there, and enough to make it profitable to continue. And we will." The staff is already working on revisions of future issues of Wireless.

"It's certainly easier to say, 'We are radio broadcasters. That's all we do.' But if you're willing to work hard and think creatively, you can create products, and performers. The key is not 'A Prairie Home Companion.' The key is the kind of thinking that has nurtured 'A Prairie Home Companion.' "