Leaders of the congressional high-tech caucus, showing off some of the nation's most advanced telecommunications systems, staged a public opinion poll via satellite yesterday with television viewers in Ohio. They got the answers they were looking for.

Subscribers to the Warner Amex QUBE cable systems in Columbus and Cincinatti found themselves listening to Rep. Tim Wirth, (D-Colo.) chairman of the House subcommittee on telecommunications, who was broadcasting to them from a makeshift television studio in a corner of the Cannon office building's caucus room.

What Wirth wanted to know was whether the viewers thought the federal government "should do more to support math and science education and research and development?" As the question was printed on their screens, viewers had the opportunity to respond instantly, using the key pads connected to their sets--the special feature of the two-way QUBE system, which has been in operation since the mid-1970s.

Three-quarters of the viewers said yes, Wirth reported. It wasn't reported how many viewers responded.

The backdrop to this interactive cable poll was an expo of high tech gee-wizardry with the well-engineered sobriquet of "ET"--for Emerging Technologies. The idea of ET, says Wirth and cosponsor Sen. Robert Packwood (R-Ore.), is to expose legislators and staff alike to some of the actual hardware components of the "technological revolution" that are being counted on to generate new jobs and growth.

There were some short circuits at this high-tech show-and-tell. MCI's offer of a free phone call anywhere in the United States was disconnected because of technical problems. But RCA Corp., American Telephone & Telegraph Co. and other acronym-laden telecommunications and computer companies succeeded in giving congressmen and their staffs a taste of the new technologies.

Motorola Inc., which hopes to provide mobile radio telephone equipment to customers in Washington and scores of other cities once regulators approve new cellular radio service, demonstrated some of its latest wares. And Time Inc.'s HBO and M/A COM showed off devices that scramble television signals to discourage piracy of pay-TV programs.

"This is the easist way to expose people to what we're doing," said James Bauer, a CBS executive showing off the videotex technology that it developed in tandem with American Bell, the AT&T equipment marketing division. Videotex technology allows a user with a terminal or specially-adapted television set to retrieve information and videogames from a central computer via the phone lines.